A Novel Fiber Optic Surface Plasmon Resonance Biosensors with Special Boronic Acid Derivative to Detect Glycoprotein

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Yang Zhang

2017-10-01

Full Text Available We proposed and demonstrated a novel tilted fiber Bragg grating (TFBG-based surface plasmon resonance (SPR label-free biosensor via a special boronic acid derivative to detect glycoprotein with high sensitivity and selectivity. TFBG, as an effective sensing element for optical sensing in near-infrared wavelengths, possess the unique capability of easily exciting the SPR effect on fiber surface which coated with a nano-scale metal layer. SPR properties can be accurately detected by measuring the variation of transmitted spectra at optical communication wavelengths. In our experiment, a 10° TFBG coated with a 50 nm gold film was manufactured to stimulate SPR on a sensor surface. To detect glycoprotein selectively, the sensor was immobilized using designed phenylboronic acid as the recognition molecule, which can covalently bond with 1,2- or 1,3-diols to form five- or six-membered cyclic complexes for attaching diol-containing biomolecules and proteins. The phenylboronic acid was synthetized with long alkyl groups offering more flexible space, which was able to improve the capability of binding glycoprotein. The proposed TFBG-SPR sensors exhibit good selectivity and repeatability with a protein concentration sensitivity up to 2.867 dB/ (mg/mL and a limit of detection (LOD of 15.56 nM.

Human platelet glycoprotein Ia. One component is only expressed on the surface of activated platelets and may be a granule constituent

International Nuclear Information System (INIS)

Bienz, D.; Clemetson, K.J.

1989-01-01

Glycoprotein Ia (GP Ia) is a relatively minor component of human blood platelets thought to be a receptor involved in collagen-induced platelet activation. However, some difficulties exist with the definition of this glycoprotein. The expression of GP Ia on resting (prostacyclin analogue-treated) and thrombin-activated platelets was compared by surface labeling with 125 I-lactoperoxidase. Intact platelets or platelets solubilized in sodium dodecyl sulfate were labeled with periodate/[ 3 H]NaBH 4 . Analysis on two-dimensional isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels showed that GP Ia is very poorly labeled in resting platelets. After activation a new spot (GP Ia*) appears with the same relative molecular mass as GP Ia under reducing conditions. GP Ia and Ia* can be clearly separated by two-dimensional nonreduced/reduced gel electrophoresis. Therefore, two glycoproteins which have been termed GP Ia exist in platelets with similar molecular weight and pI under reducing conditions. One of these (GP Ia*) is only surface-labeled when platelets are activated, indicating that it is only exposed on the surface of activated platelets. Supernatant from activated platelets contains this glycoprotein as well as other granule components. This glycoprotein is missing in platelets from two patients with collagen-response defects

Anti-beta2 glycoprotein 1 and the anti-phospholipid syndrome.

LENUS (Irish Health Repository)

Keane, Pearse A

2012-02-03

PURPOSE: To describe a patient who presented with bilateral retinal vascular occlusion and the use of anti-beta2 glycoprotein 1 (GPI) antibody testing in the diagnosis of antiphospholipid syndrome. DESIGN: Observational case report. METHODS: Hematological investigations were performed on a 49-year-old man who presented with rapid onset of bilateral severe central retinal vein occlusion. RESULTS: Lupus anticoagulant and anticardiolipin antibody testing was negative. Markedly raised titers of anti-beta2 GPI antibodies were detected on two separate occasions. CONCLUSIONS: The raised titers of anti-beta2 GPI antibodies were considered to strongly suggest an underlying diagnosis of the antiphospholipid syndrome.

Lupus anticoagulants and antiphospholipid antibodies

Science.gov (United States)

Blood clots - lupus anticoagulants; DVT - anticoagulants ... Most often, lupus anticoagulants and aPL are found in people with diseases such as systemic lupus erythematosus (SLE). Lupus anticoagulants and ...

Surface (glyco-)proteins: primary structure and crystallization under microgravity conditions

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Claus, H.; Akca, E.; Schultz, N.; Karbach, G.; Schlott, B.; Debaerdemaeker, T.; De Clercq, J.-P.; König, H.

2001-08-01

The Archaea comprise microorganisms that live under environmental extremes, like high temperature, low pH value or high salt concentration. Their cells are often covered by a single layer of (glyco)protein subunits (S-layer) in hexagonal arrangement. In order to get further hints about the molecular mechanisms of protein stabilization we compared the primary and secondary structures of archaeal S-layer (glyco)proteins. We found an increase of charged amino acids in the S-layer proteins of the extreme thermophilic species compared to their mesophilic counterparts. Our data and those of other authors suggest that ionic interactions, e.g., salt bridges seem to be played a major role in protein stabilization at high temperatures. Despite the differences in the growth optima and the predominance of some amino acids the primary structures of S-layers revealed also a significant degree of identity between phylogenetically related archaea. These obervations indicate that protein sequences of S-layers have been conserved during the evolution from extremely thermophilic to mesophilic life. To support these findings the three-dimensional structure of the S-layer proteins has to be elucidated. Recently, we described the first successful crystallization of an extreme thermophilic surface(glyco)protein under microgravity conditions.

Anticoagulant Resistance

DEFF Research Database (Denmark)

Heiberg, Ann-Charlotte

Although sewer rat control is carried out in more than 80 % of all Danish municipalities, with usage of large amounts of anticoagulant rodenticides, knowledge on anticoagulant resistance among rats living in the sewers is limited. As rat problems in urban areas are believed to be related to sewer...... problems (70-90 % in UK and DK) unawareness of resistance amongst these populations of Brown rats may constitute a future control problem and knowledge on this issue has become crucial. Rats were captured in sewers from seven different locations in the suburban area of Copenhagen. Locations was chosen...... to represent different sewer rat management strategies i) no anticoagulants for approx. 20 years ii) no anticoagulants for the last 5 years and iii) continuous control for many years. Animals were tested for resistance to bromadiolone by Blood-Clotting Response test, as bromadiolone is the most frequently used...

The interaction of protein S with the phospholipid surface is essential for the activated protein C-independent activity of protein S

NARCIS (Netherlands)

van Wijnen, M.; Stam, J. G.; van't Veer, C.; Meijers, J. C.; Reitsma, P. H.; Bertina, R. M.; Bouma, B. N.

1996-01-01

Protein S is a vitamin-K dependent glycoprotein involved in the regulation of the anticoagulant activity of activated protein C (APC). Recent data showed a direct anticoagulant role of protein S independent of APC, as demonstrated by the inhibition of prothrombinase and tenase activity both in

Combined administration of antibiotics and direct oral anticoagulants: a renewed indication for laboratory monitoring?

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Lippi, Giuseppe; Favaloro, Emmanuel J; Mattiuzzi, Camilla

2014-10-01

The recent development and marketing of novel direct oral anticoagulants (DOACs) represents a paradigm shift in the management of patients requiring long-term anticoagulation. The advantages of these compounds over traditional therapy with vitamin K antagonists include a reportedly lower risk of severe hemorrhages and the limited need for laboratory measurements. However, there are several scenarios in which testing should be applied. The potential for drug-to-drug interaction is one plausible but currently underrecognized indication for laboratory assessment of the anticoagulant effect of DOACs. In particular, substantial concern has been raised during Phase I studies regarding the potential interaction of these drugs with some antibiotics, especially those that interplay with permeability glycoprotein (P-gp) and cytochrome 3A4 (CYP3A4). A specific electronic search on clinical trials published so far confirms that clarithromycin and rifampicin significantly impair the bioavailability of dabigatran, whereas clarithromycin, erythromycin, fluconazole, and ketoconazole alter the metabolism of rivaroxaban in vivo. Because of their more recent development, no published data were found for apixaban and edoxaban, or for potential interactions of DOACs with other and widely used antibiotics. It is noteworthy, however, that an online resource based on Food and Drug Administration and social media information, reports several hemorrhagic and thrombotic events in patients simultaneously taking dabigatran and some commonly used antibiotics such as amoxicillin, cephalosporin, and metronidazole. According to these reports, the administration of antibiotics in patients undergoing therapy with DOACs would seem to require accurate evaluation as to whether dose adjustments (personalized or antibiotic class driven) of the anticoagulant drug may be advisable. This might be facilitated by direct laboratory assessments of their anticoagulant effect ex vivo. Thieme Medical Publishers

The macrophage CD163 surface glycoprotein is an erythroblast adhesion receptor

DEFF Research Database (Denmark)

Fabriek, Babs O; Polfliet, Machteld M J; Vloet, Rianka P M

2007-01-01

Erythropoiesis occurs in erythroblastic islands, where developing erythroblasts closely interact with macrophages. The adhesion molecules that govern macrophage-erythroblast contact have only been partially defined. Our previous work has implicated the rat ED2 antigen, which is highly expressed...... on the surface of macrophages in erythroblastic islands, in erythroblast binding. In particular, the monoclonal antibody ED2 was found to inhibit erythroblast binding to bone marrow macrophages. Here, we identify the ED2 antigen as the rat CD163 surface glycoprotein, a member of the group B scavenger receptor...... that it enhanced erythroid proliferation and/or survival, but did not affect differentiation. These findings identify CD163 on macrophages as an adhesion receptor for erythroblasts in erythroblastic islands, and suggest a regulatory role for CD163 during erythropoiesis....

Association between Oral Anticoagulation Knowledge ...

African Journals Online (AJOL)

Association between Oral Anticoagulation Knowledge, Anticoagulation Control, and Demographic Characteristics of Patients Attending an Anticoagulation Clinic in Saudi Arabia: A Cross-Sectional Prospective Evaluation.

Formation of high-order oligomers is required for functional bioactivity of an African bat henipavirus surface glycoprotein.

Science.gov (United States)

Behner, Laura; Zimmermann, Louisa; Ringel, Marc; Weis, Michael; Maisner, Andrea

2018-05-01

Hendra virus (HeV) and Nipah virus (NiV) are highly pathogenic henipaviruses originating from fruit bats in Australia and Asia that can cause severe infections in livestock and humans. In recent years, also African bat henipaviruses were identified at the nucleic acid level. To assess their potential to replicate in non-bat species, several studies were performed to characterize the two surface glycoproteins required for virus entry and spread by cell-cell fusion. It has been shown that surface expression and fusion-helper function of the receptor-binding G protein of Kumasi virus (KV), the prototypic Ghanaian bat henipavirus, is reduced compared to other non-African henipavirus G proteins. Immunostainings and pulse-chase analysis revealed a delayed export of KV G from the ER. As defects in oligomerization of viral glycoproteins can be responsible for limited surface transport thereby restricting the bioactivity, we analyzed the oligomerization pattern of KV G. In contrast to HeV and NiV whose G proteins are known to be expressed at a dimer-tetramer ratio of 1:1, KV G almost exclusively formed stable tetramers or higher oligomers. KV G also showed less stringent requirements for defined stalk cysteines to form dimers and tetramers. Interestingly, any changes in the oligomeric forms negatively affected the fusion-helper activity although surface expression and receptor binding was unchanged. This clearly indicates that the formation of mostly higher oligomeric KV G forms is not a deficiency responsible for ER retention, but is rather a basic structural feature essential for the bioactivity of this African bat henipavirus glycoprotein. Copyright © 2018 Elsevier B.V. All rights reserved.

The future of anticoagulation clinics.

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Macik, B Gail

2003-01-01

Anticoagulation therapy is the foundation of treatment for thromboembolic disorders; and coumarin derivatives (warfarin in the United States) are the only orally administered anticoagulant medications currently available. Due to the expense and relative difficulties associated with this route of administration, parenteral drugs are not used routinely for long-term therapy, leaving warfarin as the anticoagulant of choice in the outpatient setting. The management of warfarin is problematic, however, due the nuances of its pharmacodynamic and pharmacokinetic profile and the requirement for frequent monitoring of blood levels. Although management by anticoagulation clinics is considered the gold standard for warfarin therapy, management by an anticoagulation clinic may not be the optimal option from a clinician's view and, in many cases, may not be an option at all. Anticoagulation clinics may impinge on the doctor-patient relationship. Difficulties of communication and reimbursement are not ameliorated by a specialty clinic. Innovations in warfarin management, including patient self-management and computerized dosing programs, are alternatives for improved care that are available with or without input by an anticoagulation service. New oral drugs on the horizon do not require the same intensity of monitoring and do not present the same pharmacodynamic problems associated with warfarin. Warfarin will become obsolete in the foreseeable future. If anticoagulation clinics continue, they must re-define their role as the major part of the workload, warfarin management, disappears. To adapt, clinics must strengthen and enhance their role as coordinators and educators, and less so, managers of anticoagulation therapy.

Direct oral anticoagulants: An update.

Science.gov (United States)

Franco Moreno, Ana Isabel; Martín Díaz, Rosa María; García Navarro, María José

2017-12-30

Vitamin K antagonists were the only choice for chronic oral anticoagulation for more than half a century. Over the past few years, direct oral anticoagulants have emerged, including one direct thrombin inhibitor (dabigatran etexilate) and three factor Xa inhibitors (apixaban, edoxaban and rivaroxaban). In randomised controlled trials comparing direct oral anticoagulants with traditional vitamin K antagonists, the direct oral anticoagulants all showed a favourable benefit-risk balance in their safety and efficacy profile, in prevention of thromboembolic events in patients with atrial fibrillation and in the prevention and treatment of venous thromboembolism and acute coronary syndrome. In 2008, dabigatran was the first direct oral anticoagulant approved by the European Medicine Agency. Subsequently, rivaroxaban, apixaban and edoxaban were also authorised. This article reviews the evidence related to the use of these drugs. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

[New oral anticoagulant drugs].

Science.gov (United States)

Berkovits, Alejandro; Aizman, Andrés; Zúñiga, Pamela; Pereira, Jaime; Mezzano, Diego

2011-10-01

Thromboembolic disease (TED) is the leading cause of morbidity and mortality worldwide. The hallmark of oral long-term anticoagulant therapy has been the use of vitamin K antagonists, whose anticoagulant effect is exerted inhibiting vitamin K epoxide reductase. Warfarin and acenocoumarol are the most commonly used. In the last five years several new drugs for long term anticoagulation have been developed, which can inhibit single clotting factors with the purpose of improving drug therapeutic range and, ideally, minimizing bleeding risks. This review addresses the state of the art on the clinical use of inhibitors of activated factor X and thrombin.

The glycoprotein of measles virus

International Nuclear Information System (INIS)

Anttonen, O.; Jokinen, M.; Salmi, A.; Vainionpaeae, R.; Gahmberg, C.G.

1980-01-01

Measles virus was propagated in VERO cells and purified from the culture supernatants by two successive tartrate-density-gradient centrifugations. Surface carbohydrates were labelled both in vitro and in vivo with 3 H after treatment with galactose oxidase/NaB 3 H 4 or with [ 3 H]glucosamine. The major labelled glycoprotein in measles virions had a mol.wt. of 79000. After labelling with periodate/NaB 3 H 4 , which would result in specific labelling of sialic acid residues, the 79000-mol.wt. glycoprotein was very weakly labelled. This suggested that there is no or a very low amount of sialic acid in the virions. Further analysis of the glycoprotein showed that galactose is the terminal carbohydrate unit in the oligosaccharide, and the molecular weight of the glycopeptide obtained after Pronase digestion is about 3000. The oligosaccharide is attached to the polypeptide through an alkali-stable bond, indicating a N-glycosidic asparagine linkage. (author)

Determination of P-Glycoprotein Expression by Flow Cytometry in Hematological Malignancies

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Berkay Saraymen

2016-03-01

Full Text Available Objective: Determination the expression of P-glycoprotein is especially problematic for normal tissues because immuno­logical methods are limited in terms of sensitivity. We aimed to determine the expression of P-glycoprotein and CD34 by flow cytometry, and to evaluate the level of expression of P-glycoprotein and CD34 with unresponsive to treatment in pa­tients diagnosed with hematologic malignancy. Methods: Our study included fifty patients diagnosed with acute myeloblastic leukemia and acute lymphoblastic leuke­mia, and twenty healthy controls who were admitted to Erci­yes University Hematology-Oncology Hospital. The suspend­ed cells from bone marrow samples of patients and the pe­ripheral blood samples of healthy people were marked with P-glycoprotein phycoerythrin and CD34 FITC or PerCP Cy 5.5; and then surface expression was measured by means of flow cytometry. Results: In 6 of 30 acute myeloblastic leukemia patients P-glycoprotein and CD34 expression, in 6 of 20 acute lympho­blastic leukemia patients P-glycoprotein, in 5 of them CD34 expression were determined. A significant relation between P-glycoprotein and CD34 expressions in acute myeloblas­tic leukemia and acute lymphoblastic leukemia bone marrow samples was reported. Conclusion: Our data indicate that flow cytometry is more reliable, precise and faster than molecular methods for mea­suring P-glycoprotein expression and suggests the pos­sibility of a significant relationship between P-glycoprotein and CD34 expressions in acute myeloblastic leukemia and acute lymphoblastic leukemia bone marrow samples. The blast cells expressing CD34 on their surface along with P-glycoprotein simultaneously show that multi drug resistance 1 gene is mostly active in immature cells.

Glycoproteins of mouse vaginal epithelium: differential expression related to estrous cyclicity

DEFF Research Database (Denmark)

Horvat, B; Multhaupt, H A; Damjanov, I

1993-01-01

We used lectin overlay blotting and SDS-PAGE to analyze the estrous cycle-specific expression of mouse vaginal epithelial glycoproteins. Seven lectins chosen for their differential carbohydrate-binding specificity revealed 15 glycoproteins that showed cycle-related expression. Each lectin had...... in proestrus, coincident with the transformation of two superficial layers of vaginal squamous epithelium into mucinous cuboidal cells. Electron microscopic lectin histochemistry revealed the glycoproteins in the mucinous granules of surface cuboidal cells and in the lumen of the vagina. Our results illustrate...... the complexity of glycoconjugate synthesis in mouse vagina and reveal the distinct cycle-specific patterns of individual glycoprotein expression. These cyclic glycoproteins could serve as vaginal biochemical markers for the specific phases of the estrous cycle....

Anticoagulation period in idiopathic venous thromboembolism

International Nuclear Information System (INIS)

Farraj, Rami S.

2004-01-01

The period of anticoagulation of a first episode of idiopathic venous thromboembolism has been 6 months. It is unclear if such patients would benefit from longer treatment, as there appears to be an increased risk of recurrence after anticoagulation is stopped. In a randomized prospective study of 64 patients admitted to King Hussein Medical city, Amman, Jordan, who developed a first episode of venous thromboembolism, 32 patients were given warfarin for 24-months, while 32 patients stopped anticoagulation after completion of 6-months of therapy. Our goal was to determine the effects of extended anticoagulation on rates of recurrence of symptomatic venous thromboembolism and bleeding. The patients were followed for 12-months after stopping anticoagulation. After 24-months, 7 of the 32 patients (21%) who had standard anticoagulation for 6-months had a recurrent episode of thromboembolism compared to one of the 32 patients who received anticoagulation for 24 months (3%). Extended warfarin therapy for 24-months has resulted in an absolute risk reduction of 0.1% (p<0.05). This translates into 8 patients having to be treated for 24-months to avoid one recurrence without increasing the risk of major bleeding. Two patients in each group (6%) had major nonfatal bleeding, all 4 bleeding episodes occurring within the first 3-months of anticoagulation. After 36-months of follow up, the recurrence rate of extended warfarin therapy was only 3 patients (9%), which is a 43% relative reduction in recurrence of thromboembolism compared to standard therapy for 6-months. Patients with first episodes of idiopathic venous thromboembolism have an increased risk of recurrent venous thromboembolism and should be treated with oral anticoagulants for longer than 6-months, probably 24-months. (author)

Chronic kidney disease and anticoagulation

DEFF Research Database (Denmark)

Sciascia, Savino; Radin, Massimo; Schreiber, Karen

2017-01-01

Anticoagulation in patients with impaired kidney function can be challenging since drugs' pharmacokinetics and bioavailability are altered in this setting. Patients with chronic kidney disease (CKD) treated with conventional anticoagulant agents [vitamin K antagonist (VKA), low-molecular weight...... are eliminated via the kidneys pose additional challenges. More recently, two classes of direct oral anticoagulant agents (DOACs) have been investigated for the prevention and management of venous thromboembolic events: the direct factor Xa inhibitors rivaroxaban, apixaban and edoxaban, and the direct thrombin...

Direct oral anticoagulants and venous thromboembolism

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Massimo Franchini

2016-09-01

Full Text Available Venous thromboembolism (VTE, consisting of deep vein thrombosis and pulmonary embolism, is a major clinical concern associated with significant morbidity and mortality. The cornerstone of management of VTE is anticoagulation, and traditional anticoagulants include parenteral heparins and oral vitamin K antagonists. Recently, new oral anticoagulant drugs have been developed and licensed, including direct factor Xa inhibitors (e.g. rivaroxaban, apixaban and edoxaban and thrombin inhibitors (e.g. dabigatran etexilate. This narrative review focusses on the characteristics of these direct anticoagulants and the main results of published clinical studies on their use in the prevention and treatment of VTE.

Importance of the short cytoplasmic domain of the feline immunodeficiency virus transmembrane glycoprotein for fusion activity and envelope glycoprotein incorporation into virions

International Nuclear Information System (INIS)

Celma, Cristina C.P.; Paladino, Monica G.; Gonzalez, Silvia A.; Affranchino, Jose L.

2007-01-01

The mature form of the envelope (Env) glycoprotein of lentiviruses is a heterodimer composed of the surface (SU) and transmembrane (TM) subunits. Feline immunodeficiency virus (FIV) possesses a TM glycoprotein with a cytoplasmic tail of approximately 53 amino acids which is unusually short compared with that of the other lentiviral glycoproteins (more than 100 residues). To investigate the relevance of the FIV TM cytoplasmic domain to Env-mediated viral functions, we characterized the biological properties of a series of Env glycoproteins progressively shortened from the carboxyl terminus. All the mutant Env proteins were efficiently expressed in feline cells and processed into the SU and TM subunits. Deletion of 5 or 11 amino acids from the TM C-terminus did not significantly affect Env surface expression, fusogenic activity or Env incorporation into virions, whereas removal of 17 or 23 residues impaired Env-mediated cell-to-cell fusion. Further truncation of the FIV TM by 29 residues resulted in an Env glycoprotein that was poorly expressed at the cell surface, exhibited only 20% of the wild-type Env fusogenic capacity and was inefficiently incorporated into virions. Remarkably, deletion of the TM C-terminal 35 or 41 amino acids restored or even enhanced Env biological functions. Indeed, these mutant Env glycoproteins bearing cytoplasmic domains of 18 or 12 amino acids were found to be significantly more fusogenic than the wild-type Env and were efficiently incorporated into virions. Interestingly, truncation of the TM cytoplasmic domain to only 6 amino acids did not affect Env incorporation into virions but abrogated Env fusogenicity. Finally, removal of the entire TM cytoplasmic tail or deletion of as many as 6 amino acids into the membrane-spanning domain led to a complete loss of Env functions. Our results demonstrate that despite its relatively short length, the FIV TM cytoplasmic domain plays an important role in modulating Env-mediated viral functions

Anticoagulant Medicine: Potential for Drug-Food Interactions

Science.gov (United States)

... Medications Anticoagulants and Drug-Food Interactions Anticoagulants and Drug-Food Interactions Make an Appointment Ask a Question Refer Patient ... Jewish Health wants you to be aware these drug-food interactions when taking anticoagulant medicine. Ask your health care ...

Laboratory Assessment of the Anticoagulant Activity of Direct Oral Anticoagulants: A Systematic Review.

Science.gov (United States)

Samuelson, Bethany T; Cuker, Adam; Siegal, Deborah M; Crowther, Mark; Garcia, David A

2017-01-01

Direct oral anticoagulants (DOACs) are the treatment of choice for most patients with atrial fibrillation and/or noncancer-associated venous thromboembolic disease. Although routine monitoring of these agents is not required, assessment of anticoagulant effect may be desirable in special situations. The objective of this review was to summarize systematically evidence regarding laboratory assessment of the anticoagulant effects of dabigatran, rivaroxaban, apixaban, and edoxaban. PubMed, Embase, and Web of Science were searched for studies reporting relationships between drug levels and coagulation assay results. We identified 109 eligible studies: 35 for dabigatran, 50 for rivaroxaban, 11 for apixaban, and 13 for edoxaban. The performance of standard anticoagulation tests varied across DOACs and reagents; most assays, showed insufficient correlation to provide a reliable assessment of DOAC effects. Dilute thrombin time (TT) assays demonstrated linear correlation (r 2  = 0.67-0.99) across a range of expected concentrations of dabigatran, as did ecarin-based assays. Calibrated anti-Xa assays demonstrated linear correlation (r 2  = 0.78-1.00) across a wide range of concentrations for rivaroxaban, apixaban, and edoxaban. An ideal test, offering both accuracy and precision for measurement of any DOAC is not widely available. We recommend a dilute TT or ecarin-based assay for assessment of the anticoagulant effect of dabigatran and anti-Xa assays with drug-specific calibrators for direct Xa inhibitors. In the absence of these tests, TT or APTT is recommended over PT/INR for assessment of dabigatran, and PT/INR is recommended over APTT for detection of factor Xa inhibitors. Time since last dose, the presence or absence of drug interactions, and renal and hepatic function should impact clinical estimates of anticoagulant effect in a patient for whom laboratory test results are not available. Copyright © 2016 American College of Chest Physicians. Published by Elsevier

Use of anticoagulants in elderly patients: practical recommendations

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Helia Robert-Ebadi

2009-04-01

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

Tailoring of TiO2 films by H2SO4 treatment and UV irradiation to improve anticoagulant ability and endothelial cell compatibility.

Science.gov (United States)

Liao, Yuzhen; Li, Linhua; Chen, Jiang; Yang, Ping; Zhao, Ansha; Sun, Hong; Huang, Nan

2017-07-01

Surfaces with dual functions that simultaneously exhibit good anticoagulant ability and endothelial cell (EC) compatibility are desirable for blood contact materials. However, these dual functions have rarely been achieved by inorganic materials. In this study, titanium dioxide (TiO 2 ) films were treated by sulphuric acid (H 2 SO 4 ) and ultraviolet (UV) irradiation successively (TiO 2 H 2 SO 4 -UV), resulting in good anticoagulant ability and EC compatibility simultaneously. We found that UV irradiation improved the anticoagulant ability of TiO 2 films significantly while enhancing EC compatibility, though not significantly. The enhanced anticoagulant ability could be related to the oxidation of surface-adsorbed hydrocarbons and increased hydrophilicity. The H 2 SO 4 treatment improved the anticoagulant ability of TiO 2 films slightly, while UV irradiation improved the anticoagulant ability strongly. The enhanced EC compatibility could be related to the increased surface roughness and positive charges on the surface of the TiO 2 films. Furthermore, the time-dependent degradation of the enhanced EC compatibility and anticoagulant ability of TiO 2 H 2 SO 4 -UV was observed. In summary, TiO 2 H 2 SO 4 -UV expressed both excellent anticoagulant ability and good EC compatibility at the same time, which could be desirable for blood contact materials. However, the compatibility of TiO 2 H 2 SO 4 -UV with smooth muscle cells (SMCs) and macrophages was also improved. More effort is still needed to selectively improve EC compatibility on TiO 2 films for better re-endothelialization. Copyright © 2017 Elsevier B.V. All rights reserved.

Anticoagulation and high dose liver radiation. A preliminary report

International Nuclear Information System (INIS)

Lightdale, C.J.; Wasser, J.; Coleman, M.; Brower, M.; Tefft, M.; Pasmantier, M.

1979-01-01

Two groups of patients were observed for evidence of acute radiation hepatitis during high dose radiation to the liver. The first group of 18 patients with metastatic liver disease received an average of 4,050 rad to the whole liver. Half received anticoagulation with warfarin. One patient on anticoagulation developed evidence of acute radiation hepatitis while 2 patients did so without anticoagulation. Eleven patients with Hodgkin's disease received 4,000 rad to the left lobe of the liver during extended field radiation. Four of these 11 patients were anticoagulated to therapeutic range. Only one of the fully anticoagulated patients showed changes on liver scan consistent with radiation hepatitis whereas three did so without anticoagulation. No serious sequelae from anticoagulation occurred in either group. These preliminary data suggest that anticoagulation may be safely administered with high dose hepatic radiation and that further trials with anticoagulation are warranted

Managing reversal of direct oral anticoagulants in emergency situations Anticoagulation Education Task Force White Paper

NARCIS (Netherlands)

Ageno, Walter; Büller, Harry R.; Falanga, Anna; Hacke, Werner; Hendriks, Jeroen; Lobban, Trudie; Merino, Jose; Milojevic, Ivan S.; Moya, Francisco; van der Worp, H. Bart; Randall, Gary; Tsioufis, Konstantinos; Verhamme, Peter; Camm, A. John

2016-01-01

Anticoagulation is the cornerstone of prevention and treatment of venous thromboembolism (VTE) and stroke prevention in patients with atrial fibrillation (AF). However, the mechanisms by which anticoagulants confer therapeutic benefit also increase the risk of bleeding. As such, reversal strategies

Fatal consequences of synergistic anticoagulation

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Sen P

2018-05-01

Full Text Available Objective: Novel oral anticoagulants (NOACs are increasingly being preferred by clinicians (and patients because they have a wide therapeutic window and therefore do not require monitoring of anticoagulant effect. Herein, we describe the unfortunate case of a patient who had fatal consequences as a result of switching from warfarin to rivaroxaban. Case Summary: A 90-year-old Caucasian woman, with atrial fibrillation on chronic anticoagulation with warfarin, was admitted to the hospital for pneumonia. She was treated with levofloxacin. In the same admission, her warfarin was switched to rivaroxaban. On Day 3 after the switch, her INR was found to be 6, and she developed a cervical epidural hematoma from C2 to C7. She ultimately developed respiratory arrest, was put on comfort care and died. Discussion: Rivaroxaban and warfarin are known to have a synergistic anticoagulant effect, usually seen shortly after switching. Antibiotics also increase the effects of warfarin by the inhibition of metabolizing isoenzymes. It is hypothesized that these two effects led to the fatal cervical spinal hematoma. Conclusion: The convenience of a wide therapeutic window and no requirement of laboratory monitoring makes the NOACs a desirable option for anticoagulation. However, there is lack of data and recommendations on how to transition patients from Warfarin to NOACs or even how to transition from one NOAC to another. Care should be taken to ensure continuous monitoring of anticoagulation when stopping, interrupting or switching between NOACS to avoid the possibility of fatal bleeding and strokes.

Does plasmin have anticoagulant activity?

Directory of Open Access Journals (Sweden)

Jane Hoover-Plow

2010-03-01

Full Text Available Jane Hoover-PlowJoseph J Jacobs Center for Thrombosis and Vascular Biology, Departments of Cardiovascular Medicine and Molecular Cardiology, Lerner Research Institute Cleveland Clinic, Ohio, USAAbstract: The coagulation and fibrinolytic pathways regulate hemostasis and thrombosis, and an imbalance in these pathways may result in pathologic hemophilia or thrombosis. The plasminogen system is the primary proteolytic pathway for fibrinolysis, but also has important proteolytic functions in cell migration, extracellular matrix degradation, metalloproteinase activation, and hormone processing. Several studies have demonstrated plasmin cleavage and inactivation of several coagulation factors, suggesting plasmin may be not only be the primary fibrinolytic enzyme, but may have anticoagulant properties as well. The objective of this review is to examine both in vitro and in vivo evidence for plasmin inactivation of coagulation, and to consider whether plasmin may act as a physiological regulator of coagulation. While several studies have demonstrated strong evidence for plasmin cleavage and inactivation of coagulation factors FV, FVIII, FIX, and FX in vitro, in vivo evidence is lacking for a physiologic role for plasmin as an anticoagulant. However, inactivation of coagulation factors by plasmin may be useful as a localized anticoagulant therapy or as a combined thrombolytic and anticoagulant therapy.Keywords: thrombosis, anticoagulant, cardiovascular disease, plasminogen’s protease, blood

Glycoproteins and sialyl transferase of human B lymphoblastoid cell lines

International Nuclear Information System (INIS)

Lui, S.W.L.; Ng, M.H.

1980-01-01

We used two radiolabeling methods to study glycoproteins on the surface of lymphoblastoid cells. One of the methods affects tritiation of residues which are oxidized with galactose oxidase and the other causes tritiation of neuraminic acid residues. This approach was shown to allow a better resolution of cell surface glycoproteins than if either method were used alone. Glycoproteins of B 1 - 19 cells which harbor the Epstein-Barr virus genomes were compared with those of its parental cell line, BJAB, which does not harbor the viral genomes. These studies did not reveal a unique viral protein. A 28,000 mol. wt. glycoprotein was found to be the most prominent neuraminic acidlabeled product of B 1 - 19 cells and also of the two other cell lines, Raji and Ly38, which harbor the EBV genomes. A similar molecular weight species from BJAB cells identified by galactose oxidase labeling might be deficient in neuraminic acid residues as it was poorly labeled by the periodate oxidation method. The neuraminic acid content and level of sialyl transferase of BJAB cells were found to be lower than those of the other cell lines studied. (auth.)

Secondary poisoning of owls by anticoagulant rodenticides

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Mendenhall, Vivian M.; Pank, L.F.

1980-01-01

Anticoagulants-compounds that prevent clotting of the blood-are extensively used for control of small mammal pests. The potential secondary hazards of 6 anticoagulant rodenticides to birds of prey were examined in this study. Whole rats or mice were killed with each anticoagulant and were fed to 1-3 species of owls. Owls died of hemorrhaging after feeding on rats killed with bromadiolone, brodifacoum, or diphacinone; sublethal hemorrhaging occurred in owls fed rats killed with difenacoum. These results demonstrate potential secondary hazards of 4 anticoagulants to avian predators. No abnormalities were observed in owls fed rats killed with fumarin and chlorophacinone

The hydroxyapatite-binding regions of a rat salivary glycoprotein.

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Embery, G; Green, D R

1989-09-01

The regions of a salivary sulphated glycoprotein which are involved in its attachment to hydroxyapatite (Biogel HTP) have been characterised. The sulphated glycoprotein, a 35S-labelled preparation from mixed palatal and buccal minor gland secretions of the rat was bound onto hydroxyapatite and the resultant glycoprotein-hydroxyapatite complex was sequentially digested with pronase E and alpha-L-fucosidase, a treatment which released 86.8% +/- 1.7% of the radioactivity of the initially bound glycoprotein. The fragments which remained attached to the hydroxyapatite after enzymic digestion were fractionated on Sephadex G-25 and analysed for carbohydrate and amino acid components. A range of amino acids were detected which could reflect both glycosylated and non-glycosylated-binding regions. Sialic acid, although considered to be involved in the attachment process was not detected in any of the fragments remaining after enzymic digestion, a finding which provides indirect evidence that the enzymically liberated products do not subsequently re-attach to the hydroxyapatite surface. The notable feature of the fractions with average Mr estimated at 1000 or less is the high proportion of N-acetylhexosamine and N-acetylgalactosamine. It is apparent that the hexosamine residues, which normally bear the ester sulphate moieties of sulphated glycoproteins, play an important role in the attachment of sulphated glycoproteins to hydroxyapatite.

Effects of computer-assisted oral anticoagulant therapy

DEFF Research Database (Denmark)

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

2012-01-01

: Patients randomized to computer-assisted anticoagulation and the CoaguChek® system reached the therapeutic target range after 8 days compared to 14 days by prescriptions from physicians (p = 0.04). Time spent in the therapeutic target range did not differ between groups. The median INR value measured...... prescribed by physicians, and the total time spent within the therapeutic target range was similar. Thus computer-assisted oral anticoagulant therapy may reduce the cost of anticoagulation therapy without lowering the quality. INR values measured by CoaguChek® were reliable compared to measurements......UNLABELLED: BACKGROUND: Computer-assistance and self-monitoring lower the cost and may improve the quality of anticoagulation therapy. The main purpose of this clinical investigation was to use computer-assisted oral anticoagulant therapy to improve the time to reach and the time spent within...

Bridging Anticoagulation

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... clinical centers in the United States, Canada, and Brazil. A more detailed description of the study is ... Your Personal Message Send Message Share on Social Media Bridging Anticoagulation The BRIDGE Study Investigators Circulation. 2012; ...

The mythology of anticoagulation therapy interruption for dental surgery.

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Wahl, Michael J

2018-01-01

Continuous anticoagulation therapy is used to prevent heart attacks, strokes, and other embolic complications. When patients receiving anticoagulation therapy undergo dental surgery, a decision must be made about whether to continue anticoagulation therapy and risk bleeding complications or briefly interrupt anticoagulation therapy and increase the risk of developing embolic complications. Results from decades of studies of thousands of dental patients receiving anticoagulation therapy reveal that bleeding complications requiring more than local measures for hemostasis have been rare and never fatal. However, embolic complications (some of which were fatal and others possibly permanently debilitating) sometimes have occurred in patients whose anticoagulation therapy was interrupted for dental procedures. Although there is now virtually universal consensus among national medical and dental groups and other experts that anticoagulation therapy should not be interrupted for most dental surgery, there are still some arguments made supporting anticoagulation therapy interruption. An analysis of these arguments shows them to be based on a collection of myths and half-truths rather than on logical scientific conclusions. The time has come to stop anticoagulation therapy interruption for dental procedures. Copyright © 2018 American Dental Association. Published by Elsevier Inc. All rights reserved.

Defining glycoprotein cancer biomarkers by MS in conjunction with glycoprotein enrichment.

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Song, Ehwang; Mechref, Yehia

2015-01-01

Protein glycosylation is an important and common post-translational modification. More than 50% of human proteins are believed to be glycosylated to modulate the functionality of proteins. Aberrant glycosylation has been correlated to several diseases, such as inflammatory skin diseases, diabetes mellitus, cardiovascular disorders, rheumatoid arthritis, Alzheimer's and prion diseases, and cancer. Many approved cancer biomarkers are glycoproteins which are not highly abundant proteins. Therefore, effective qualitative and quantitative assessment of glycoproteins entails enrichment methods. This chapter summarizes glycoprotein enrichment methods, including lectin affinity, immunoaffinity, hydrazide chemistry, hydrophilic interaction liquid chromatography, and click chemistry. The use of these enrichment approaches in assessing the qualitative and quantitative changes of glycoproteins in different types of cancers are presented and discussed. This chapter highlights the importance of glycoprotein enrichment techniques for the identification and characterization of new reliable cancer biomarkers.

Assessing Bleeding Risk in Patients Taking Anticoagulants

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Shoeb, Marwa; Fang, Margaret C.

2013-01-01

Anticoagulant medications are commonly used for the prevention and treatment of thromboembolism. Although highly effective, they are also associated with significant bleeding risks. Numerous individual clinical factors have been linked to an increased risk of hemorrhage, including older age, anemia, and renal disease. To help quantify hemorrhage risk for individual patients, a number of clinical risk prediction tools have been developed. These risk prediction tools differ in how they were derived and how they identify and weight individual risk factors. At present, their ability to effective predict anticoagulant-associated hemorrhage remains modest. Use of risk prediction tools to estimate bleeding in clinical practice is most influential when applied to patients at the lower spectrum of thromboembolic risk, when the risk of hemorrhage will more strongly affect clinical decisions about anticoagulation. Using risk tools may also help counsel and inform patients about their potential risk for hemorrhage while on anticoagulants, and can identify patients who might benefit from more careful management of anticoagulation. PMID:23479259

The peanut lectin-binding glycoproteins of human epidermal keratinocytes

International Nuclear Information System (INIS)

Morrison, A.I.; Keeble, S.; Watt, F.M.

1988-01-01

The peanut lectin (PNA) is known to bind more strongly to keratinocytes that are undergoing terminal differentiation than to proliferating keratinocytes. In order to investigate the significance of this change in cell-surface carbohydrate authors have identified the PNA-binding glycoproteins of cultured human keratinocytes and antibodies against them. Two heavily glycosylated bands of 110 and 250 kDa were resolved by PAGE of [ 14 C]galactose- or [ 14 C]mannose- and [ 14 C]glucosamine-labeled cell extracts eluted with galactose from PNA affinity columns. The higher molecular weight band was also detected on PNA blots of unlabeled cell extracts transferred to nitrocellulose. Both bands were sensitive to pronase digestion, but only the 250-kDa band was digested with trypsin. A rabbit antiserum that we prepared (anti-PNA-gp) immunoprecipitated both bands from cell extracts. In contrast to PNA, anti-PNA-gp bound equally to proliferating and terminally differentiating cells, indicating that some epitope(s) of the PNA-binding glycoproteins is present on the cell surface prior to terminal differentiation. When keratinocytes grown as a monolayer in low-calcium medium were switched to medium containing 2 mM calcium ions in order to induce desmosome formation and stratification, there was a dramatic redistribution of the PNA-binding glycoproteins, which became concentrated at the boundaries between cells. This may suggest a role for the glycoproteins in cell-cell interactions during stratification

MARINE LEECH ANTICOAGULANT DIVERSITY AND EVOLUTION.

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Tessler, Michael; Marancik, David; Champagne, Donald; Dove, Alistair; Camus, Alvin; Siddall, Mark E; Kvist, Sebastian

2018-03-16

Leeches (Annelida: Hirudinea) possess powerful salivary anticoagulants and, accordingly, are frequently employed in modern, authoritative medicine. Members of the almost exclusively marine family Piscicolidae account for 20% of leech species diversity, and feed on host groups (e.g., sharks) not encountered by their freshwater and terrestrial counterparts. Moreover, some species of Ozobranchidae feed on endangered marine turtles and have been implicated as potential vectors for the tumor-associated turtle herpesvirus. In spite of their ecological importance and unique host associations, there is a distinct paucity of data regarding the salivary transcriptomes of either of these families. Using next generation sequencing, we profiled transcribed, putative anticoagulants and other salivary bioactive compounds that have previously been linked to bloodfeeding from 7 piscicolid species (3 elasmobranch-feeders; 4 non-cartilaginous fish-feeders) and 1 ozobranchid species (2 samples). In total, 149 putative anticoagulants and bioactive loci were discovered in varying constellations throughout the different samples. The putative anticoagulants showed a broad spectrum of described antagonistic pathways, such as inhibition of factor Xa and platelet aggregation, that likely have similar bioactive roles in marine fish and turtles. A transcript with homology to ohanin, originally isolated from king cobras, was found in Cystobranchus vividus but is otherwise unknown from leeches. Estimation of selection pressures for the putative anticoagulants recovered evidence for both positive and purifying selection along several isolated branches in the gene trees and positive selection was also estimated for a few select codons in a variety of marine species. Similarly, phylogenetic analyses of the amino acid sequences for several anticoagulants indicated divergent evolution.

Reversing anticoagulant effects of novel oral anticoagulants: role of ciraparantag, andexanet alfa, and idarucizumab

Directory of Open Access Journals (Sweden)

Hu TY

2016-02-01

Full Text Available Tiffany Y Hu,1 Vaibhav R Vaidya,2 Samuel J Asirvatham2,31Mayo Medical School, 2Division of Cardiovascular Diseases, Department of Internal Medicine, 3Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, MN, USAAbstract: Novel oral anticoagulants (NOACs are increasingly used in clinical practice, but lack of commercially available reversal agents is a major barrier for mainstream use of these therapies. Specific antidotes to NOACs are under development. Idarucizumab (aDabi-Fab, BI 655075 is a novel humanized mouse monoclonal antibody that binds dabigatran and reverses its anticoagulant effect. In a recent Phase III study (Reversal Effects of Idarucizumab on Active Dabigatran, a 5 g intravenous infusion of idarucizumab resulted in the normalization of dilute thrombin time in 98% and 93% of the two groups studied, with normalization of ecarin-clotting time in 89% and 88% patients. Two other antidotes, andexanet alfa (PRT064445 and ciraparantag (PER977 are also under development for reversal of NOACs. In this review, we discuss commonly encountered management issues with NOACs such as periprocedural management, laboratory monitoring of anticoagulation, and management of bleeding. We review currently available data regarding specific antidotes to NOACs with respect to pharmacology and clinical trials.Keywords: novel oral anticoagulant, dabigatran, idarucizumab, reversal

Anticoagulated patient's perception of their illness, their beliefs about the anticoagulant therapy prescribed and the relationship with adherence: impact of novel oral anticoagulant therapy - study protocol for The Switching Study: a prospective cohort study.

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Auyeung, Vivian; Patel, Jignesh P; Abdou, John K; Vadher, Bipin; Bonner, Lynda; Brown, Alison; Roberts, Lara N; Patel, Raj K; Arya, Roopen

2016-01-01

Anticoagulant therapy is prescribed for millions of patients worldwide for the prevention and treatment of both arterial and venous thrombosis. Historically, only vitamin K antagonists have been available for clinicians to prescribe. The anticoagulation landscape is changing. The recent availability of the novel oral anticoagulants overcome many of the disadvantages associated with vitamin K antagonists. However the lack of formal monitoring and clinic follow-up is a concern for clinicians, as medication adherence is being assumed, which is known to decline in patients prescribed medications for chronic conditions. The switching study is a programme of work investigating the association between medication adherence and patient's beliefs about anticoagulation therapy (warfarin and subsequently novel oral anticoagulants), together with beliefs about their illness and anticoagulation related quality of life. The anticoagulation database at King's College Hospital will be interrogated and two groups of patients will be identified; those with a time in therapeutic range on warfarin of ≥75 % and those beliefs about medications compared. Those patients in the time in therapeutic range beliefs about medications, re-evaluated on the novel agent. The results from these sub-studies, will inform a clinical pathway to support patients on these novel agents, which will be evaluated in an independent group of patients. The results from the switching study will be used to develop a clinical pathway to support patient's prescribed novel oral anticoagulant therapy long-term.

Survey of Botulinum Toxin Injections in Anticoagulated Patients: Korean Physiatrists' Preference in Controlling Anticoagulation Profile Prior to Intramuscular Injection.

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Jang, Yongjun; Park, Geun-Young; Park, Jihye; Choi, Asayeon; Kim, Soo Yeon; Boulias, Chris; Phadke, Chetan P; Ismail, Farooq; Im, Sun

2016-04-01

To evaluate Korean physiatrists' practice of performing intramuscular botulinum toxin injection in anticoagulated patients and to assess their preference in controlling the bleeding risk before injection. As part of an international collaboration survey study, a questionnaire survey was administered to 100 Korean physiatrists. Physiatrists were asked about their level of experience with botulinum toxin injection, the safe international normalized ratio range in anticoagulated patients undergoing injection, their tendency for injecting into deep muscles, and their experience of bleeding complications. International normalized ratio injection by 41% of the respondents. Thirty-six respondents replied that the international normalized ratio should be lowered to sub-therapeutic levels before injection, and 18% of the respondents reported that anticoagulants should be intentionally withheld and discontinued prior to injection. In addition, 20%-30% of the respondents answered that they were uncertain whether they should perform the injection regardless of the international normalized ratio values. About 69% of the respondents replied that they did have any standardized protocols for performing botulinum toxin injection in patients using anticoagulants. Only 1 physiatrist replied that he had encountered a case of compartment syndrome. In accordance with the lack of consensus in performing intramuscular botulinum toxin injection in anticoagulated patients, our survey shows a wide range of practices among many Korean physiatrists; they tend to avoid botulinum toxin injection in anticoagulated patients and are uncertain about how to approach these patients. The results of this study emphasize the need for formulating a proper international consensus on botulinum toxin injection management in anticoagulated patients.

The pharmacology of recombinant hirudin, a new anticoagulant ...

African Journals Online (AJOL)

A new anticoagulant, recombinant hirudin, was given to healthy volunteers (5 per test dose) in single .intravenous doses of 0,01, 0,02, 0,04, 0,07 and 0,1 mg/kg to study its anticoagulant effects, how it was tolerated and its pharmacokinetics. Hirudin proved to be a potent anticoagulant with important effects on thrombin ...

The Sperm-surface glycoprotein, SGP, is necessary for fertilization in the frog, Xenopus laevis.

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Nagai, Keita; Ishida, Takuya; Hashimoto, Takafumi; Harada, Yuichirou; Ueno, Shuichi; Ueda, Yasushi; Kubo, Hideo; Iwao, Yasuhiro

2009-06-01

To identify a molecule involved in sperm-egg plasma membrane binding at fertilization, a monoclonal antibody against a sperm-surface glycoprotein (SGP) was obtained by immunizing mice with a sperm membrane fraction of the frog, Xenopus laevis, followed by screening of the culture supernatants based on their inhibitory activity against fertilization. The fertilization of both jellied and denuded eggs was effectively inhibited by pretreatment of sperm with intact anti-SGP antibody as well as its Fab fragment, indicating that the antibody recognizes a molecule on the sperm's surface that is necessary for fertilization. On Western blots, the anti-SGP antibody recognized large molecules, with molecular masses of 65-150 kDa and minor smaller molecules with masses of 20-28 kDa in the sperm membrane vesicles. SGP was distributed over nearly the entire surface of the sperm, probably as an integral membrane protein in close association with microfilaments. More membrane vesicles containing SGP bound to the surface were found in the animal hemisphere compared with the vegetal hemisphere in unfertilized eggs, but the vesicle-binding was not observed in fertilized eggs. These results indicate that SGP mediates sperm-egg membrane binding and is responsible for the establishment of fertilization in Xenopus.

Optimal duration of anticoagulation in patients with venous thromboembolism.

Science.gov (United States)

Prandoni, Paolo; Piovella, Chiara; Spiezia, Luca; Dalla Valle, Fabio; Pesavento, Raffaele

2011-07-01

The risk of recurrent venous thromboembolism (VTE) approaches 40 per cent of all patients after 10 yr of follow up. This risk is higher in patients with permanent risk factors of thrombosis such as active cancer, prolonged immobilization from medical diseases, and antiphospholipid syndrome; in carriers of several thrombophilic abnormalities, including deficiencies of natural anticoagulants; and in patients with unprovoked presentation. Patients with permanent risk factors of thrombosis should receive indefinite anticoagulation, consisting of subtherapeutic doses of low molecular weight heparin in cancer patients, and oral anticoagulants in all other conditions. Patients whose VTE is triggered by major surgery or trauma should be offered three months of anticoagulation. Patients with unprovoked VTE, including carriers of thrombophilia, and those whose thrombotic event is associated with minor risk factors (such as hormonal treatment, minor injuries, long travel) should receive at least three months of anticoagulation. The decision as to go on or discontinue anticoagulation after this period should be individually tailored and balanced against the haemorrhagic risk. Post-baseline variables, such as the D-dimer determination and the ultrasound assessment of residual thrombosis can help identify those patients in whom anticoagulation can be safely discontinued. As a few emerging anti-Xa and anti-IIa compounds seem to induce fewer haemorrhagic complications than conventional anticoagulation, while preserving at least the same effectiveness, these have the potential to open new scenarios for decisions regarding the duration of anticoagulation in patients with VTE.

Release of Glycoprotein (GP1 from the Tegumental Surface of Taenia solium by Phospholipase C from Clostridium perfringens Suggests a Novel Protein-Anchor to Membranes

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Abraham Landa

2010-01-01

Full Text Available In order to explore how molecules are linked to the membrane surface in larval Taenia solium, whole cysticerci were incubated in the presence of phospholipase C from Clostridium perfringens (PLC. Released material was collected and analyzed in polyacrylamide gels with sodium dodecyl sulfate. Two major bands with apparent molecular weights of 180 and 43 kDa were observed. Western blot of released material and localization assays in cysticerci tissue sections using antibodies against five known surface glycoproteins of T. solium cysticerci indicated that only one, previously called GP1, was released. Similar localization studies using the lectins wheat-germ-agglutinin and Concanavalin A showed that N-acetyl-D-glucosamine, N-acetylneuraminic, sialic acid, αmethyl-D-mannoside, D-manose/glucose, and N-acetyl-D-glucosamine residues are abundantly present on the surface. On the other hand, we find that treatment with PLC releases molecules from the surface; they do not reveal Cross Reacting Determinant (CRD, suggesting a novel anchor to the membrane for the glycoprotein GP1.

Impact of time to treatment on the effects of bivalirudin vs. glycoprotein IIb/IIIa inhibitors and heparin in patients undergoing primary percutaneous coronary intervention

DEFF Research Database (Denmark)

Schoos, Mikkel; De Luca, Giuseppe; Dangas, George D

2016-01-01

AIMS: In the HORIZONS-AMI trial, bivalirudin compared to unfractionated heparin (UFH) plus a glycoprotein IIb/IIIa inhibitor (GPI) improved net clinical outcomes in patients undergoing primary percutaneous coronary intervention (PCI) at the cost of an increased rate of acute stent thrombosis. We...... sought to examine whether these effects are dependent on time to treatment. METHODS AND RESULTS: The interaction between anticoagulation regimen and symptom onset to first balloon inflation time (SBT) on the 30-day and three-year rates of major adverse cardiac events (MACE) was examined in 3...

Platelet Glycoprotein Ib-IX and Malignancy

Science.gov (United States)

2010-09-01

provide a unique microenvironment supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation...process and can initiate the formation of a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib... Platelet Glycoprotein Ib-IX and Malignancy PRINCIPAL INVESTIGATOR: Jerry Ware, Ph.D

EMA: a developmentally regulated cell-surface glycoprotein of CNS neurons that is concentrated at the leading edge of growth cones.

Science.gov (United States)

Baumrind, N L; Parkinson, D; Wayne, D B; Heuser, J E; Pearlman, A L

1992-08-01

To identify cell-surface molecules that mediate interactions between neurons and their environment during neural development, we used monoclonal antibody techniques to define a developmentally regulated antigen in the central nervous system of the mouse. The antibody we produced (2A1) immunolabels cells throughout the central nervous system; we analyzed its distribution in the developing cerebral cortex, where it is expressed on cells very soon after they complete mitosis and leave the periventricular proliferative zone. Expression continues into adult life. The antibody also labels the epithelium of the choroid plexus and the renal proximal tubules, but does not label neurons of the peripheral nervous system in the dorsal root ganglia. In dissociated cell culture of embryonic cerebral cortex, 2A1 labels the surface of neurons but not glia. Immunolabeling of neurons in tissue culture is particularly prominent on the edge of growth cones, including filopodia and the leading edge of lamellipodia, when observed with either immunofluorescence or freeze-etch immunoelectron microscopy. Immunopurification with 2A1 of a CHAPS-extracted membrane preparation from brains of neonatal mice produces a broad (32-36 kD) electrophoretic band and a less prominent 70 kD band that are sensitive to N-glycosidase but not endoglycosidase H. Thus the 2A1 antibody recognizes a developmentally regulated, neuronal cell surface glycoprotein (or glycoproteins) with complex N-linked oligosaccharide side chains. We have termed the glycoprotein antigen EMA because of its prominence on the edge membrane of growth cones. EMA is similar to the M6 antigen (Lagenaur et al: J. Neurobiol. 23:71-88, 1992) in apparent molecular weight, distribution in tissue sections, and immunoreactivity on Western blots, suggesting that the two antigens are similar or identical. Expression of EMA is a very early manifestation of neuronal differentiation; its distribution on growth cones suggests a role in mediating the

Evaluation of hematuria in anticoagulated patients

International Nuclear Information System (INIS)

Cuttino, J.T.; Clark, R.L.

1986-01-01

To determine the efficacy of investigating hematuria in anticoagulated patients the authors examined records of 25 consecutive patients with hematuria who were on an anticoagulation regimen with sodium warfarin (Coumadin) for various thromboembolic disorders. All had undergone intravenous urography (IVU) and 12 had undergone cystoscopy. Potential bleeding sources were discovered in 14 patients by IVU and in seven patients by cystoscopy. Disorders found were renal stones (4), transitional carcinoma (1), lymphoma (1), retroperitoneal hematoma (1), bladder tumors (2), calcified renal mass (1), hemorrhagic cystitis (2), and enlarged prostate (7). In 18 (72%) patients, the findings on IVU and/or cystoscopy were abnormal. Hematuria is a serious symptom that warrants investigation in anticoagulated as well as nonanticoagulated patients

Anticoagulation knowledge in patients with atrial fibrillation: An Australian survey.

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Obamiro, Kehinde O; Chalmers, Leanne; Lee, Kenneth; Bereznicki, Bonnie J; Bereznicki, Luke R E

2018-03-01

Atrial fibrillation (AF) is the most commonly diagnosed arrhythmia in clinical practice, and is associated with a significant medical and economic burden. Anticoagulants reduce the risk of stroke and systemic embolism by approximately two-thirds compared with no therapy. Knowledge regarding anticoagulant therapy can influence treatment outcomes in patients with AF. To measure the level of anticoagulation knowledge in patients with AF taking oral anticoagulants (OACs), investigate the association between patient-related factors and anticoagulation knowledge, and compare these results in patients taking warfarin and direct-acting oral anticoagulant (DOACs). Participants were recruited for an online survey via Facebook. Survey components included the Anticoagulation Knowledge Tool, the Perception of Anticoagulant Treatment Questionnaires (assessing treatment expectations, convenience and satisfaction), a modified Cancer Information Overload scale and the Morisky Medication Adherence Scale. Treatment groups were compared and predictors of OAC knowledge were identified. Participants taking warfarin had a higher knowledge score compared with those taking DOACs (n = 386, 73% ± 13% vs 66% ± 14%, Pcounselling sessions to help identify and resolve knowledge deficits. © 2018 John Wiley & Sons Ltd.

Evidence-Based Management of Anticoagulant Therapy

Science.gov (United States)

Schulman, Sam; Witt, Daniel M.; Vandvik, Per Olav; Fish, Jason; Kovacs, Michael J.; Svensson, Peter J.; Veenstra, David L.; Crowther, Mark; Guyatt, Gordon H.

2012-01-01

Background: High-quality anticoagulation management is required to keep these narrow therapeutic index medications as effective and safe as possible. This article focuses on the common important management questions for which, at a minimum, low-quality published evidence is available to guide best practices. Methods: The methods of this guideline follow those described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement. Results: Most practical clinical questions regarding the management of anticoagulation, both oral and parenteral, have not been adequately addressed by randomized trials. We found sufficient evidence for summaries of recommendations for 23 questions, of which only two are strong rather than weak recommendations. Strong recommendations include targeting an international normalized ratio of 2.0 to 3.0 for patients on vitamin K antagonist therapy (Grade 1B) and not routinely using pharmacogenetic testing for guiding doses of vitamin K antagonist (Grade 1B). Weak recommendations deal with such issues as loading doses, initiation overlap, monitoring frequency, vitamin K supplementation, patient self-management, weight and renal function adjustment of doses, dosing decision support, drug interactions to avoid, and prevention and management of bleeding complications. We also address anticoagulation management services and intensive patient education. Conclusions: We offer guidance for many common anticoagulation-related management problems. Most anticoagulation management questions have not been adequately studied. PMID:22315259

Galectin-3 induces clustering of CD147 and integrin-β1 transmembrane glycoprotein receptors on the RPE cell surface.

Directory of Open Access Journals (Sweden)

Claudia S Priglinger

Full Text Available Proliferative vitreoretinopathy (PVR is a blinding disease frequently occurring after retinal detachment surgery. Adhesion, migration and matrix remodeling of dedifferentiated retinal pigment epithelial (RPE cells characterize the onset of the disease. Treatment options are still restrained and identification of factors responsible for the abnormal behavior of the RPE cells will facilitate the development of novel therapeutics. Galectin-3, a carbohydrate-binding protein, was previously found to inhibit attachment and spreading of retinal pigment epithelial cells, and thus bares the potential to counteract PVR-associated cellular events. However, the identities of the corresponding cell surface glycoprotein receptor proteins on RPE cells are not known. Here we characterize RPE-specific Gal-3 containing glycoprotein complexes using a proteomic approach. Integrin-β1, integrin-α3 and CD147/EMMPRIN, a transmembrane glycoprotein implicated in regulating matrix metalloproteinase induction, were identified as potential Gal-3 interactors on RPE cell surfaces. In reciprocal immunoprecipitation experiments we confirmed that Gal-3 associated with CD147 and integrin-β1, but not with integrin-α3. Additionally, association of Gal-3 with CD147 and integrin-β1 was observed in co-localization analyses, while integrin-α3 only partially co-localized with Gal-3. Blocking of CD147 and integrin-β1 on RPE cell surfaces inhibited binding of Gal-3, whereas blocking of integrin-α3 failed to do so, suggesting that integrin-α3 is rather an indirect interactor. Importantly, Gal-3 binding promoted pronounced clustering and co-localization of CD147 and integrin-β1, with only partial association of integrin-α3. Finally, we show that RPE derived CD147 and integrin-β1, but not integrin-α3, carry predominantly β-1,6-N-actyl-D-glucosamine-branched glycans, which are high-affinity ligands for Gal-3. We conclude from these data that extracellular Gal-3 triggers

Galectin-3 Induces Clustering of CD147 and Integrin-β1 Transmembrane Glycoprotein Receptors on the RPE Cell Surface

Science.gov (United States)

Priglinger, Claudia S.; Szober, Christoph M.; Priglinger, Siegfried G.; Merl, Juliane; Euler, Kerstin N.; Kernt, Marcus; Gondi, Gabor; Behler, Jennifer; Geerlof, Arie; Kampik, Anselm; Ueffing, Marius; Hauck, Stefanie M.

2013-01-01

Proliferative vitreoretinopathy (PVR) is a blinding disease frequently occurring after retinal detachment surgery. Adhesion, migration and matrix remodeling of dedifferentiated retinal pigment epithelial (RPE) cells characterize the onset of the disease. Treatment options are still restrained and identification of factors responsible for the abnormal behavior of the RPE cells will facilitate the development of novel therapeutics. Galectin-3, a carbohydrate-binding protein, was previously found to inhibit attachment and spreading of retinal pigment epithelial cells, and thus bares the potential to counteract PVR-associated cellular events. However, the identities of the corresponding cell surface glycoprotein receptor proteins on RPE cells are not known. Here we characterize RPE-specific Gal-3 containing glycoprotein complexes using a proteomic approach. Integrin-β1, integrin-α3 and CD147/EMMPRIN, a transmembrane glycoprotein implicated in regulating matrix metalloproteinase induction, were identified as potential Gal-3 interactors on RPE cell surfaces. In reciprocal immunoprecipitation experiments we confirmed that Gal-3 associated with CD147 and integrin-β1, but not with integrin-α3. Additionally, association of Gal-3 with CD147 and integrin-β1 was observed in co-localization analyses, while integrin-α3 only partially co-localized with Gal-3. Blocking of CD147 and integrin-β1 on RPE cell surfaces inhibited binding of Gal-3, whereas blocking of integrin-α3 failed to do so, suggesting that integrin-α3 is rather an indirect interactor. Importantly, Gal-3 binding promoted pronounced clustering and co-localization of CD147 and integrin-β1, with only partial association of integrin-α3. Finally, we show that RPE derived CD147 and integrin-β1, but not integrin-α3, carry predominantly β-1,6-N-actyl-D-glucosamine-branched glycans, which are high-affinity ligands for Gal-3. We conclude from these data that extracellular Gal-3 triggers clustering of CD147 and

Reversal of target-specific oral anticoagulants

Science.gov (United States)

Siegal, D.M.; Cuker, Adam

2014-01-01

Target-specific oral anticoagulants (TSOACs) provide safe and effective anticoagulation for the prevention and treatment of thrombosis in a variety of clinical settings by interfering with the activity of thrombin (dabigatran) or factor Xa (rivaroxaban, apixaban, edoxaban, betrixaban). Although TSOACs have practical advantages over vitamin K antagonists (VKAs), there are currently no antidotes to reverse their anticoagulant effect. Herein we summarize the available evidence for TSOAC reversal using nonspecific and specific reversal agents. We discuss important limitations of existing evidence, which is derived from studies in human volunteers, animal models and in vitro experiments. Studies evaluating the safety and efficacy of reversal agents on clinical outcomes such as bleeding and mortality in patients with TSOAC-associated bleeding are needed. PMID:24880102

Glycoprotein expression by adenomatous polyps of the colon

Science.gov (United States)

Roney, Celeste A.; Xie, Jianwu; Xu, Biying; Jabour, Paul; Griffiths, Gary; Summers, Ronald M.

2008-03-01

Colon cancer is the second leading cause of cancer related deaths in the United States. Specificity in diagnostic imaging for detecting colorectal adenomas, which have a propensity towards malignancy, is desired. Adenomatous polyp specimens of the colon were obtained from the mouse model of colorectal cancer called adenomatous polyposis coli-multiple intestinal neoplasia (APC Min). Histological evaluation, by the legume protein Ulex europaeus agglutinin I (UEA-1), determined expression of the glycoprotein α-L-fucose. FITC-labelled UEA-1 confirmed overexpression of the glycoprotein by the polyps on fluorescence microscopy in 17/17 cases, of which 13/17 included paraffin-fixed mouse polyp specimens. In addition, FITC-UEA-1 ex vivo multispectral optical imaging of 4/17 colonic specimens displayed over-expression of the glycoprotein by the polyps, as compared to non-neoplastic mucosa. Here, we report the surface expression of α-L-fucosyl terminal residues by neoplastic mucosal cells of APC specimens of the mouse. Glycoprotein expression was validated by the carbohydrate binding protein UEA-1. Future applications of this method are the development of agents used to diagnose cancers by biomedical imaging modalities, including computed tomographic colonography (CTC). UEA-1 targeting to colonic adenomas may provide a new avenue for the diagnosis of colorectal carcinoma by CT imaging.

Glycoprotein H of herpes simplex virus type 1 requires glycoprotein L for transport to the surfaces of insect cells

NARCIS (Netherlands)

Westra, DF; Glazenburg, KL; Harmsen, MC; Tiran, A; Scheffer, AJ; Welling, GW; The, TH; WellingWester, S

In mammalian cells, formation of heterooligomers consisting of the glycoproteins H and L (gH and gL) of herpes simplex virus type 1 is essential for the cell-to-cell spread of virions and for the penetration of virions into cells. We examined whether formation of gH1/gL1 heterooligomers and cell

Rat macrophages: membrane glycoproteins in differentiation and function

NARCIS (Netherlands)

van den Berg, T. K.; Döpp, E. A.; Dijkstra, C. D.

2001-01-01

Macrophages (mphi) play a crucial role in the immune system. The rat offers unique advantages for studying the biology of mphi. Firstly, monoclonal antibodies (mAb) against many rat mphi surface glycoproteins have become available. These have not only demonstrated a considerable heterogeneity among

The cell surface expressed nucleolin is a glycoprotein that triggers calcium entry into mammalian cells

International Nuclear Information System (INIS)

Losfeld, Marie-Estelle; Khoury, Diala El; Mariot, Pascal; Carpentier, Mathieu; Krust, Bernard; Briand, Jean-Paul; Mazurier, Joel; Hovanessian, Ara G.; Legrand, Dominique

2009-01-01

Nucleolin is an ubiquitous nucleolar phosphoprotein involved in fundamental aspects of transcription regulation, cell proliferation and growth. It has also been described as a shuttling molecule between nucleus, cytosol and the cell surface. Several studies have demonstrated that surface nucleolin serves as a receptor for various extracellular ligands implicated in cell proliferation, differentiation, adhesion, mitogenesis and angiogenesis. Previously, we reported that nucleolin in the extranuclear cell compartment is a glycoprotein containing N- and O-glycans. In the present study, we show that glycosylation is an essential requirement for surface nucleolin expression, since it is prevented when cells are cultured in the presence of tunicamycin, an inhibitor of N-glycosylation. Accordingly, surface but not nuclear nucleolin is radioactively labeled upon metabolic labeling of cells with [ 3 H]glucosamine. Besides its well-demonstrated role in the internalization of specific ligands, here we show that ligand binding to surface nucleolin could also induce Ca 2+ entry into cells. Indeed, by flow cytometry, microscopy and patch-clamp experiments, we show that the HB-19 pseudopeptide, which binds specifically surface nucleolin, triggers rapid and intense membrane Ca 2+ fluxes in various types of cells. The use of several drugs then indicated that Store-Operated Ca 2+ Entry (SOCE)-like channels are involved in the generation of these fluxes. Taken together, our findings suggest that binding of an extracellular ligand to surface nucleolin could be involved in the activation of signaling pathways by promoting Ca 2+ entry into cells

Risk of gastrointestinal bleeding during anticoagulant treatment.

Science.gov (United States)

Lanas-Gimeno, Aitor; Lanas, Angel

2017-06-01

Gastrointestinal bleeding (GIB) is a major problem in patients on oral anticoagulation therapy. This issue has become even more pressing since the introduction of direct oral anticoagulants (DOACs) in 2009. Areas covered: Here we review current evidence related to GIB associated with oral anticoagulants, focusing on randomized controlled trials, meta-analyses, and post-marketing observational studies. Dabigatran 150 mg twice daily and rivaroxaban 20 mg once daily increase the risk of GIB compared to warfarin. The risk increase with edoxaban is dose-dependent, while apixaban shows apparently, no increased risk. We summarize what is known about GIB risk factors for individual anticoagulants, the location of GIB in patients taking these compounds, and prevention strategies that lower the risk of GIB. Expert opinion: Recently there has been an important shift in the clinical presentation of GIB. Specifically, upper GIB has decreased with the decreased incidence of peptic ulcers due to the broad use of proton pump inhibitors and the decreased prevalence of H. pylori infections. In contrast, the incidence of lower GIB has increased, due in part to colonic diverticular bleeding and angiodysplasia in the elderly. In this population, the addition of oral anticoagulation therapy, especially DOACs, seems to increase the risk of lower GIB.

An unusual dependence of human herpesvirus-8 glycoproteins-induced cell-to-cell fusion on heparan sulfate

International Nuclear Information System (INIS)

Tiwari, Vaibhav; Darmani, Nissar A.; Thrush, Gerald R.; Shukla, Deepak

2009-01-01

Human herpesvirus-8 (HHV-8) is known to interact with cell surface heparan sulfate (HS) for entry into a target cell. Here we investigated the role of HS during HHV-8 glycoproteins-induced cell fusion. Interestingly, the observed fusion demonstrated an unusual dependence on HS as evident from following lines of evidence: (1) a significant reduction in cell-to-cell fusion occurred when target cells were treated with heparinase; (2) in a competition assay, when the effector cells expressing HHV-8 glycoproteins were challenged with soluble HS, cell-to-cell fusion was reduced; and, (3) co-expression of HHV-8 glycoproteins gH-gL on target cells resulted in inhibition of cell surface HS expression. Taken together, our results indicate that cell surface HS can play an additional role during HHV-8 pathogenesis.

An unusual dependence of human herpesvirus-8 glycoproteins-induced cell-to-cell fusion on heparan sulfate

Energy Technology Data Exchange (ETDEWEB)

Tiwari, Vaibhav [Department of Ophthalmology, University of Illinois at Chicago, Chicago, IL 60612 (United States); Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612 (United States); Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific and College of Optometry, Western University of Health Sciences, Pomona, CA 91766 (United States); Darmani, Nissar A.; Thrush, Gerald R. [Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific and College of Optometry, Western University of Health Sciences, Pomona, CA 91766 (United States); Shukla, Deepak, E-mail: dshukla@uic.edu [Department of Ophthalmology, University of Illinois at Chicago, Chicago, IL 60612 (United States); Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612 (United States)

2009-12-18

Human herpesvirus-8 (HHV-8) is known to interact with cell surface heparan sulfate (HS) for entry into a target cell. Here we investigated the role of HS during HHV-8 glycoproteins-induced cell fusion. Interestingly, the observed fusion demonstrated an unusual dependence on HS as evident from following lines of evidence: (1) a significant reduction in cell-to-cell fusion occurred when target cells were treated with heparinase; (2) in a competition assay, when the effector cells expressing HHV-8 glycoproteins were challenged with soluble HS, cell-to-cell fusion was reduced; and, (3) co-expression of HHV-8 glycoproteins gH-gL on target cells resulted in inhibition of cell surface HS expression. Taken together, our results indicate that cell surface HS can play an additional role during HHV-8 pathogenesis.

Anticoagulant activity of ginger ( Zingiber officinale Rosc ...

African Journals Online (AJOL)

Background: Herbal medicines with anticoagulant therapeutic claims could serve as veritable sources of new oral anticoagulant drugs with possible wider safety margins than the currently available ones. Objectives: This work was aimed at evaluating a Ginger Rhizome Methanolic Extract in vivo in rats for its potential ...

Developmental localization and the role of hydroxyproline rich glycoproteins during somatic embryogenesis of banana (Musa spp. AAA

Directory of Open Access Journals (Sweden)

Menzel Diedrik

2011-02-01

Full Text Available Abstract Background Hydroxyproline rich glycoproteins (HRGPs are implicated to have a role in many aspects of plant growth and development but there is limited knowledge about their localization and function during somatic embryogenesis of higher plants. In this study, the localization and function of hydroxyproline rich glycoproteins in embryogenic cells (ECs and somatic embryos of banana were investigated by using immunobloting and immunocytochemistry with monoclonal JIM11 and JIM20 antibodies as well as by treatment with 3,4-dehydro-L-proline (3,4-DHP, an inhibitor of extensin biosynthesis, and by immunomodulation with the JIM11 antibody. Results Immunofluorescence labelling of JIM11 and JIM20 hydroxyproline rich glycoprotein epitopes was relatively weak in non-embryogenic cells (NECs, mainly on the edge of small cell aggregates. On the other hand, hydroxyproline rich glycoprotein epitopes were found to be enriched in early embryogenic cells as well as in various developmental stages of somatic embryos. Embryogenic cells (ECs, proembryos and globular embryos showed strong labelling of hydroxyproline rich glycoprotein epitopes, especially in their cell walls and outer surface layer, so-called extracellular matrix (ECM. This hydroxyproline rich glycoprotein signal at embryo surfaces decreased and/or fully disappeared during later developmental stages (e.g. pear-shaped and cotyledonary stages of embryos. In these later developmental embryogenic stages, however, new prominent hydroxyproline rich glycoprotein labelling appeared in tri-cellular junctions among parenchymatic cells inside these embryos. Overall immunofluorescence labelling of late stage embryos with JIM20 antibody was weaker than that of JIM11. Western blot analysis supported the above immunolocalization data. The treatment with 3,4-DHP inhibited the development of embryogenic cells and decreased the rate of embryo germination. Embryo-like structures, which developed after 3,4-DHP

Overexpression of human virus surface glycoprotein precursors induces cytosolic unfolded protein response in Saccharomyces cerevisiae

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Sasnauskas Kęstutis

2011-05-01

Full Text Available Abstract Background The expression of human virus surface proteins, as well as other mammalian glycoproteins, is much more efficient in cells of higher eukaryotes rather than yeasts. The limitations to high-level expression of active viral surface glycoproteins in yeast are not well understood. To identify possible bottlenecks we performed a detailed study on overexpression of recombinant mumps hemagglutinin-neuraminidase (MuHN and measles hemagglutinin (MeH in yeast Saccharomyces cerevisiae, combining the analysis of recombinant proteins with a proteomic approach. Results Overexpressed recombinant MuHN and MeH proteins were present in large aggregates, were inactive and totally insoluble under native conditions. Moreover, the majority of recombinant protein was found in immature form of non-glycosylated precursors. Fractionation of yeast lysates revealed that the core of viral surface protein aggregates consists of MuHN or MeH disulfide-linked multimers involving eukaryotic translation elongation factor 1A (eEF1A and is closely associated with small heat shock proteins (sHsps that can be removed only under denaturing conditions. Complexes of large Hsps seem to be bound to aggregate core peripherally as they can be easily removed at high salt concentrations. Proteomic analysis revealed that the accumulation of unglycosylated viral protein precursors results in specific cytosolic unfolded protein response (UPR-Cyto in yeast cells, characterized by different action and regulation of small Hsps versus large chaperones of Hsp70, Hsp90 and Hsp110 families. In contrast to most environmental stresses, in the response to synthesis of recombinant MuHN and MeH, only the large Hsps were upregulated whereas sHsps were not. Interestingly, the amount of eEF1A was also increased during this stress response. Conclusions Inefficient translocation of MuHN and MeH precursors through ER membrane is a bottleneck for high-level expression in yeast. Overexpression of

Postpartum wound and bleeding complications in women who received peripartum anticoagulation.

Science.gov (United States)

Limmer, Jane S; Grotegut, Chad A; Thames, Elizabeth; Dotters-Katz, Sarah K; Brancazio, Leo R; James, Andra H

2013-07-01

The objective of this study was to compare wound and bleeding complications between women who received anticoagulation after cesarean delivery due to history of prior venous thromboembolic disease, arterial disease, or being a thrombophilia carrier with adverse pregnancy outcome, to women not receiving anticoagulation. Women in the Duke Thrombosis Center Registry who underwent cesarean delivery during 2003-2011 and received postpartum anticoagulation (anticoagulation group, n=77), were compared with a subset of women who delivered during the same time period, but did not receive anticoagulation (no anticoagulation group, n=77). The no anticoagulation group comprised women who were matched to the anticoagulation group by age, body mass index, type of cesarean (no labor vs. labor), and date of delivery. Bleeding and wound complications were compared between the two groups. A multivariable logistic regression model was constructed to determine if anticoagulation was an independent predictor of wound complication. Women who received anticoagulation during pregnancy had a greater incidence of wound complications compared to those who did not (30% vs. 8%, p<0.001). Using multivariable logistic regression, while controlling for race, diabetes, chorioamnionitis, and aspirin use, anticoagulation predicted the development of any wound complication (OR 5.8, 95% CI 2.2, 17.6), but there were no differences in the mean estimated blood loss at delivery (782 vs. 778 ml, p=0.91), change in postpartum hematocrit (5.4 vs. 5.2%, p=0.772), or percent of women receiving blood products (6.5 vs. 1.3%, p=0.209) between the two groups. Anticoagulation following cesarean delivery is associated with an increased risk of post-cesarean wound complications, but not other postpartum bleeding complications. Copyright © 2013 Elsevier Ltd. All rights reserved.

Antithrombotic/anticoagulant and anticancer activities of selected ...

African Journals Online (AJOL)

Antithrombotic/anticoagulant and anticancer activities of selected medicinal plants from South Africa. NLA Kee, N Mnonopi, H Davids, RJ Naudé, CL Frost. Abstract. Nine plants available in the Eastern Cape Province of South Africa were tested for antithrombotic and/or anticoagulant activity. Organic (methanol) and aqueous ...

Excessive anticoagulation with warfarin or phenprocoumon may have multiple causes

DEFF Research Database (Denmark)

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

2012-01-01

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

Citrate Anticoagulation during Continuous Renal Replacement Therapy.

Science.gov (United States)

Ricci, Davide; Panicali, Laura; Facchini, Maria Grazia; Mancini, Elena

2017-01-01

During extracorporeal dialysis, some anticoagulation strategy is necessary to prevent the coagulation of blood. Heparin has historically been used as an anticoagulant because of its efficacy combined with low cost. However, a variable incidence of hemorrhagic complications (5-30%) has been documented in patients undergoing continuous renal replacement therapy (CRRT) with heparin as an anticoagulant. Citrate has anticoagulation properties secondary to its ability to chelate calcium, which is necessary for the coagulation cascade. Citrate may thus be used in a regional anticoagulation (RCA), limited to the extracorporeal circuit of CRRT, to avoid systemic anticoagulation. Recent meta-analysis confirmed the advantage of RCA over heparin in terms of incidence of bleeding during CRRT. Moreover, an increase in filter lifespan is documented, with a secondary advantage in reaching the prescribed dialysis dose. In our experience, we could confirm this positive effect. In fact, with a progressive increase in the proportion of CRRT with citrate as RCA, we obtained a reduction in the number of filters used for every 72 h of treatment (from 2.4 in 2011 to 1.3 in 2015), and most importantly, a reduction in the difference between the prescribed and delivered dialysis doses (from 22 to 7%). Citrate has an intense effect on the acid-base balance as well, if fully metabolized through the Krebs cycle, due to the production of bicarbonate. Even more severely ill patients, such as those with liver dysfunction, may be treated with RCA without severe complications, because modern machines for CRRT are equipped with simple systems that are able to manage the citrate infusion and control the calcium levels, with minimal risks of metabolic derangements. © 2017 S. Karger AG, Basel.

Anticoagulant therapy and its impact on dental patients: a review.

Science.gov (United States)

Thean, D; Alberghini, M

2016-06-01

Several new oral anticoagulants have been studied in the past decade, and have now started to enter the market. These drugs are reported to be as effective as, or more effective than, warfarin. In Australia, the Therapeutic Goods Administration has approved dabigatran, rivaroxaban and apixaban. The use of these newer anticoagulants is likely to increase in time, and it is important for dentists to have a sound understanding of the mechanisms of action, reversal strategies, and management guidelines for patients taking oral anticoagulants. This article discusses the process of coagulation, available anticoagulants and their monitoring and reversal, and provides clinical advice on the management of patients on anticoagulants who require dental treatment. © 2016 Australian Dental Association.

Pathology consultation on anticoagulation monitoring: factor X-related assays.

Science.gov (United States)

Wool, Geoffrey D; Lu, Chuanyi M

2013-11-01

To review various anticoagulation therapies and related laboratory monitoring issues, with a focus on factor X-related chromogenic assays. A case-based approach is used to review pertinent published literatures and product inserts of anticoagulation drugs and to look back on clinical use of factor X-related chromogenic assays. The number of anticoagulants available to clinicians has increased greatly in the past decade. Whether and how these anticoagulants should be monitored are areas of uncertainty for clinicians, which can lead to misuse of laboratory assays and suboptimal patient management. Factor X-related assays are of particular concern because of the similar and often confusing test names. Based on a common clinical case scenario and literature review regarding anticoagulant monitoring, an up-to-date discussion and review of the various factor X-related assays are provided, focusing on the differences in test designs and clinical utilities between the chromogenic anti-Xa and chromogenic factor X activity assays. Anticoagulation therapy and related laboratory monitoring are rapidly evolving areas of clinical practices. A good knowledge of relevant laboratory assays and their clinical applications is necessary to help optimize patient care.

Design and synthesis of an antigenic mimic of the Ebola glycoprotein

OpenAIRE

Rutledge, Ryan D.; Huffman, Brian J.; Cliffel, David E.; Wright, David W.

2008-01-01

An antigenic mimic of the Ebola glycoprotein was synthesized and tested for its ability to be recognized by an anti-Ebola glycoprotein antibody. Epitope-mapping procedures yielded a suitable epitope that, when presented on the surface of a nanoparticle, forms a structure that is recognized by an antibody specific for the native protein. This mimic-antibody interaction has been quantitated through ELISA and QCM-based methods and yielded an affinity (Kd = 12 × 10−6 M) within two orders of magni...

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

International Nuclear Information System (INIS)

Liu Yun; Yang Yun; Wu Feng

2010-01-01

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

An unusual dependence of human herpesvirus-8 Glycoproteins-induced cell-to-cell fusion on heparan sulfate

Science.gov (United States)

Tiwari, Vaibhav; Darmani, Nissar A.; Thrush, Gerald R.; Shukla, Deepak

2009-01-01

Human herpes virus 8 (HHV-8) is known to interact with cell surface heparan sulfate (HS) for entry into a target cell. Here we investigated the role of HS during HHV-8 glycoproteins induced cell fusion. Interestingly, the observed fusion demonstrated an unusual dependence on HS as evident from following lines of evidence: 1) a significant reduction in cell-to-cell fusion occurred when target cells were treated with heparinase; 2) in a competition assay, when the effector cells expressing HHV-8 glycoproteins were challenged with soluble HS, cell-to-cell fusion was reduced; and, 3) coexpression of HHV-8 glycoproteins gH-gL on target cells resulted in inhibition of cell surface HS expression. Taken together, our results indicate that cell surface HS can play an additional role during HHV-8 pathogenesis. PMID:19747451

The RSV F and G glycoproteins interact to form a complex on the surface of infected cells

International Nuclear Information System (INIS)

Low, Kit-Wei; Tan, Timothy; Ng, Ken; Tan, Boon-Huan; Sugrue, Richard J.

2008-01-01

In this study, the interaction between the respiratory syncytial virus (RSV) fusion (F) protein, attachment (G) protein, and small hydrophobic (SH) proteins was examined. Immunoprecipitation analysis suggested that the F and G proteins exist as a protein complex on the surface of RSV-infected cells, and this conclusion was supported by ultracentrifugation analysis that demonstrated co-migration of surface-expressed F and G proteins. Although our analysis provided evidence for an interaction between the G and SH proteins, no evidence was obtained for a single protein complex involving all three of the virus proteins. These data suggest the existence of multiple virus glycoprotein complexes within the RSV envelope. Although the stimulus that drives RSV-mediated membrane fusion is unknown, the association between the G and F proteins suggest an indirect role for the G protein in this process

The glycoproteins of Marburg and Ebola virus and their potential roles in pathogenesis.

Science.gov (United States)

Feldmann, H; Volchkov, V E; Volchkova, V A; Klenk, H D

1999-01-01

Filoviruses cause systemic infections that can lead to severe hemorrhagic fever in human and non-human primates. The primary target of the virus appears to be the mononuclear phagocytic system. As the virus spreads through the organism, the spectrum of target cells increases to include endothelial cells, fibroblasts, hepatocytes, and many other cells. There is evidence that the filovirus glycoprotein plays an important role in cell tropism, spread of infection, and pathogenicity. Biosynthesis of the glycoprotein forming the spikes on the virion surface involves cleavage by the host cell protease furin into two disulfide linked subunits GP1 and GP2. GP1 is also shed in soluble form from infected cells. Different strains of Ebola virus show variations in the cleavability of the glycoprotein, that may account for differences in pathogenicity, as has been observed with influenza viruses and paramyxoviruses. Expression of the spike glycoprotein of Ebola virus, but not of Marburg virus, requires transcriptional editing. Unedited GP mRNA yields the nonstructural glycoprotein sGP, which is secreted extensively from infected cells. Whether the soluble glycoproteins GP1 and sGP interfere with the humoral immune response and other defense mechanisms remains to be determined.

[Secondary osteoporosis induced by anticoagulants?].

Science.gov (United States)

Riess, H; Loew, A; Himmelreich, G

2001-07-01

Generalized osteoporosis is a result of different causes and pathogenic mechanisms, which often combine forces to become clinically relevant. Among the different exogenic factors, drugs play an important role, frequently in connection with other factors such as immobilization or pregnancy. It has been suggested that anticoagulation therapy with heparins or coumarins may induce osteoporotic changes or enhance the development of osteoporosis for other reasons. According to in vitro experiments, preclinical trials, and clinical investigations, it seems reasonable to assume that heparins induce increased bone loss in a time- and dose-related manner. Low-molecular-weight heparins most likely have less effect on bone turnover when compared to unfractionated heparin. Oral anticoagulation therapy with vitamin K-antagonists is believed to have a weak effect on induction of osteoporosis, but clinical studies are contradictory. In spite of the fact that a relevant effect of these drugs on the induction of osteoporosis is questionable, it must be taken into consideration that anticoagulant drugs may enhance the negative effects on bone density of other risk factors capable of inducing osteoporosis such as immobilization, pregnancy, or endocrinological disorders.

Recent Progress in Electrochemical Biosensors for Glycoproteins

Directory of Open Access Journals (Sweden)

Uichi Akiba

2016-12-01

Full Text Available This review provides an overview of recent progress in the development of electrochemical biosensors for glycoproteins. Electrochemical glycoprotein sensors are constructed by combining metal and carbon electrodes with glycoprotein-selective binding elements including antibodies, lectin, phenylboronic acid and molecularly imprinted polymers. A recent trend in the preparation of glycoprotein sensors is the successful use of nanomaterials such as graphene, carbon nanotube, and metal nanoparticles. These nanomaterials are extremely useful for improving the sensitivity of glycoprotein sensors. This review focuses mainly on the protocols for the preparation of glycoprotein sensors and the materials used. Recent improvements in glycoprotein sensors are discussed by grouping the sensors into several categories based on the materials used as recognition elements.

Cost effectiveness of novel oral anticoagulants for stroke prevention in atrial fibrillation depending on the quality of warfarin anticoagulation control.

Science.gov (United States)

Janzic, Andrej; Kos, Mitja

2015-04-01

Vitamin K antagonists, such as warfarin, are standard treatments for stroke prophylaxis in patients with atrial fibrillation. Patient outcomes depend on quality of warfarin management, which includes regular monitoring and dose adjustments. Recently, novel oral anticoagulants (NOACs) that do not require regular monitoring offer an alternative to warfarin. The aim of this study was to evaluate whether cost effectiveness of NOACs for stroke prevention in atrial fibrillation depends on the quality of warfarin control. We developed a Markov decision model to simulate warfarin treatment outcomes in relation to the quality of anticoagulation control, expressed as percentage of time in the therapeutic range (TTR). Standard treatment with adjusted-dose warfarin and improved anticoagulation control by genotype-guided dosing were compared with dabigatran, rivaroxaban, apixaban and edoxaban. The analysis was performed from the Slovenian healthcare payer perspective using 2014 costs. In the base case, the incremental cost-effectiveness ratio for apixaban, dabigatran and edoxaban was below the threshold of €25,000 per quality-adjusted life-years compared with adjusted-dose warfarin with a TTR of 60%. The probability that warfarin was a cost-effective option was around 1%. This percentage rises as the quality of anticoagulation control improves. At a TTR of 70%, warfarin was the preferred treatment in half the iterations. The cost effectiveness of NOACs for stroke prevention in patients with nonvalvular atrial fibrillation who are at increased risk for stroke is highly sensitive to warfarin anticoagulation control. NOACs are more likely to be cost-effective options in settings with poor warfarin management than in settings with better anticoagulation control, where they may not represent good value for money.

Net clinical benefit of combination anticoagulant and antiplatelet therapy versus anticoagulation alone in atrial fibrillation patients: Results from the amadeus trial

NARCIS (Netherlands)

Lane, Deirdre; Kamphuisen, Pieter; Minini, Pascal; De Peuter, Olaf R.; Buller, Harry R.; Lip, Gregory Y. H.

2010-01-01

Background: To compare the effect of combination anticoagulant and antiplatelet (AP) therapy with anticoagulation alone on stroke and bleeding risk in atrial fibrillation (AF) patients and examine predictors of clinically relevant bleeding. Methods: Post-hoc analysis of 4576 AF patients [mean (SD)

Development of glycoprotein capture-based label-free method for the high-throughput screening of differential glycoproteins in hepatocellular carcinoma.

Science.gov (United States)

Chen, Rui; Tan, Yexiong; Wang, Min; Wang, Fangjun; Yao, Zhenzhen; Dong, Liwei; Ye, Mingliang; Wang, Hongyang; Zou, Hanfa

2011-07-01

A robust, reproducible, and high throughput method was developed for the relative quantitative analysis of glycoprotein abundances in human serum. Instead of quantifying glycoproteins by glycopeptides in conventional quantitative glycoproteomics, glycoproteins were quantified by nonglycosylated peptides derived from the glycoprotein digest, which consists of the capture of glycoproteins in serum samples and the release of nonglycopeptides by trypsin digestion of captured glycoproteins followed by two-dimensional liquid chromatography-tandem MS analysis of released peptides. Protein quantification was achieved by comparing the spectrum counts of identified nonglycosylated peptides of glycoproteins between different samples. This method was demonstrated to have almost the same specificity and sensitivity in glycoproteins quantification as capture at glycopeptides level. The differential abundance of proteins present at as low as nanogram per milliliter levels was quantified with high confidence. The established method was applied to the analysis of human serum samples from healthy people and patients with hepatocellular carcinoma (HCC) to screen differential glycoproteins in HCC. Thirty eight glycoproteins were found with substantial concentration changes between normal and HCC serum samples, including α-fetoprotein, the only clinically used marker for HCC diagnosis. The abundance changes of three glycoproteins, i.e. galectin-3 binding protein, insulin-like growth factor binding protein 3, and thrombospondin 1, which were associated with the development of HCC, were further confirmed by enzyme-linked immunosorbent assay. In conclusion, the developed method was an effective approach to quantitatively analyze glycoproteins in human serum and could be further applied in the biomarker discovery for HCC and other cancers.

Optical sensing of anticoagulation status: Towards point-of-care coagulation testing.

Directory of Open Access Journals (Sweden)

Diane M Tshikudi

Full Text Available Anticoagulant overdose is associated with major bleeding complications. Rapid coagulation sensing may ensure safe and accurate anticoagulant dosing and reduce bleeding risk. Here, we report the novel use of Laser Speckle Rheology (LSR for measuring anticoagulation and haemodilution status in whole blood. In the LSR approach, blood from 12 patients and 4 swine was placed in disposable cartridges and time-varying intensity fluctuations of laser speckle patterns were measured to quantify the viscoelastic modulus during clotting. Coagulation parameters, mainly clotting time, clot progression rate (α-angle and maximum clot stiffness (MA were derived from the clot viscoelasticity trace and compared with standard Thromboelastography (TEG. To demonstrate the capability for anticoagulation sensing in patients, blood samples from 12 patients treated with warfarin anticoagulant were analyzed. LSR clotting time correlated with prothrombin and activated partial thromboplastin time (r = 0.57-0.77, p<0.04 and all LSR parameters demonstrated good correlation with TEG (r = 0.61-0.87, p<0.04. To further evaluate the dose-dependent sensitivity of LSR parameters, swine blood was spiked with varying concentrations of heparin, argatroban and rivaroxaban or serially diluted with saline. We observed that anticoagulant treatments prolonged LSR clotting time in a dose-dependent manner that correlated closely with TEG (r = 0.99, p<0.01. LSR angle was unaltered by anticoagulation whereas TEG angle presented dose-dependent diminution likely linked to the mechanical manipulation of the clot. In both LSR and TEG, MA was largely unaffected by anticoagulation, and LSR presented a higher sensitivity to increased haemodilution in comparison to TEG (p<0.01. Our results establish that LSR rapidly and accurately measures the response of various anticoagulants, opening the opportunity for routine anticoagulation monitoring at the point-of-care or for patient self-testing.

Oral Anticoagulant Use After Bariatric Surgery: A Literature Review and Clinical Guidance.

Science.gov (United States)

Martin, Karlyn A; Lee, Craig R; Farrell, Timothy M; Moll, Stephan

2017-05-01

Bariatric surgery may alter the absorption, distribution, metabolism, or elimination (disposition) of orally administered drugs via changes to the gastrointestinal tract anatomy, body weight, and adipose tissue composition. As some patients who have undergone bariatric surgery will need therapeutic anticoagulation for various indications, appropriate knowledge is needed regarding anticoagulant drug disposition and resulting efficacy and safety in this population. We review general considerations about oral drug disposition in patients after bariatric surgery, as well as existing literature on oral anticoagulation after bariatric surgery. Overall, available evidence on therapeutic anticoagulation is very limited, and individual drug studies are necessary to learn how to safely and effectively use the direct oral anticoagulants. Given the sparsity of currently available data, it appears most prudent to use warfarin with international normalized ratio monitoring, and not direct oral anticoagulants, when full-dose anticoagulation is needed after bariatric surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

Dynamic bioactive stimuli-responsive polymeric surfaces

Science.gov (United States)

Pearson, Heather Marie

This dissertation focuses on the design, synthesis, and development of antimicrobial and anticoagulant surfaces of polyethylene (PE), polypropylene (PP), and poly(tetrafluoroethylene) (PTFE) polymers. Aliphatic polymeric surfaces of PE and PP polymers functionalized using click chemistry reactions by the attachment of --COOH groups via microwave plasma reactions followed by functionalization with alkyne moieties. Azide containing ampicillin (AMP) was synthesized and subsequently clicked into the alkyne prepared PE and PP surfaces. Compared to non-functionalized PP and PE surfaces, the AMP clicked surfaces exhibited substantially enhanced antimicrobial activity against Staphylococcus aureus bacteria. To expand the biocompatibility of polymeric surface anticoagulant attributes, PE and PTFE surfaces were functionalized with pH-responsive poly(2-vinyl pyridine) (P2VP) and poly(acrylic acid) (PAA) polyelectrolyte tethers terminated with NH2 and COOH groups. The goal of these studies was to develop switchable stimuli-responsive polymeric surfaces that interact with biological environments and display simultaneous antimicrobial and anticoagulant properties. Antimicrobial AMP was covalently attached to --COOH terminal ends of protected PAA, while anticoagulant heparin (HEP) was attached to terminal --NH2 groups of P2VP. When pH 5.5, they collapse while the PAA segments extend. Such surfaces, when exposed to Staphylococcus aureus, inhibit bacterial growth due to the presence of AMP, as well as are effective anticoagulants due to the presence of covalently attached HEP. Comparison of these "dynamic" pH responsive surfaces with "static" surfaces terminated with AMP entities show significant enhancement of longevity and surface activity against microbial film formation. The last portion of this dissertation focuses on the covalent attachment of living T1 and Φ11 bacteriophages (phages) on PE and PTFE surface. This was accomplished by carbodiimide coupling between --COOH

[Drug compliance of patients on anticoagulant treatment].

Science.gov (United States)

Gadó, Klára; Kocsis, Eszter; Zelkó, Romána; Hankó, Balázs; Kovácsné Balogh, Judit; Forczig, Mónika; Domján, Gyula

2015-08-09

Despite several therapeutic possibilities the morbidity and mortality of thromboembolic disorders remain high. Improving drug compliance - i. e. keeping up the doctor's prescriptions - may be an effective tool to reach better results. To improve patients' compliance, the risk factors of non-compliance should be recognized. Among these patients' fear of adverse effects of drugs, their lack of knowledge about their illness and medication, forgetfulness, and other social, economic factors may be the most important. Furthermore, adherence may be worsened when the patient feels that the decision has been made over his/her head. Sustained medical adherence is important because anticoagulation may be a life-long treatment. The new oral anticoagulants make the matter of compliance to be current. These new type of drugs do not need regular laboratory monitoring and, therefore, compliance cannot be strictly followed. There are several studies concerning drug compliance to anticoagulant medications. Improvement of adherence is based on regular patient education after reviewing the factors of non-compliance, which needs teamwork with important roles of doctors, pharmacists, dietetics and nurses. Careful and accurate work of the participants of primary care might be complemented by the activity of anticoagulant clinics.

Underuse of Anticoagulation in Older Patients with Atrial Fibrillation and CHADS2 Score ≥ 2: Are We Doing Better Since the Marketing of Direct Oral Anticoagulants?

Science.gov (United States)

Henrard, Séverine; Vandenabeele, Caroline; Marien, Sophie; Boland, Benoit; Dalleur, Olivia

2017-11-01

Our objectives were to (1) describe the evolution of the underuse of anticoagulants in older people with atrial fibrillation (AF) and a CHADS 2 score ≥ 2 since direct oral anticoagulants (DOACs) were introduced to the market and (2) describe factors associated with this underuse. We conducted a retrospective cross-sectional study including geriatric patients admitted during the pre-DOAC (2008-2011) and post-DOAC (2013-2015) periods in an academic hospital in Belgium. Five inclusion criteria were met: age ≥ 75 years, diagnosis of AF, indication for anticoagulation (CHADS 2 score ≥ 2), risk of functional decline (Identification of Seniors At Risk [ISAR] score ≥ 2), and comprehensive geriatric assessment. The use of anticoagulants and antiplatelets at home before admission was recorded. Risks of stroke and bleeding were calculated using CHADS 2 and HEMORR 2 HAGES scores, respectively. Three different logistic regression models were performed to describe the evolution of and factors associated with the underuse of anticoagulants after DOAC marketing. Anticoagulant underuse, present in 209 of 614 (34%) geriatric patients with AF, was lower in patients with a history of stroke (28.5%) or congestive heart failure (26.9%) but higher in those receiving antiplatelets (56.2%) and in older individuals. Anticoagulant underuse decreased significantly from the pre-DOAC (37.3%) to the post-DOAC (29.7%) era, as shown by two analyses using propensity scores. In older patients with AF, anticoagulant underuse was mainly associated with antiplatelet use. Anticoagulant underuse and antiplatelet use have both decreased since DOAC marketing. Underuse of anticoagulants was still a concern for three in ten geriatric patients with AF at high risk of stroke (CHADS 2 score ≥ 2).

Anticoagulant Preferences and Concerns among Venous Thromboembolism Patients.

Science.gov (United States)

Lutsey, Pamela L; Horvath, Keith J; Fullam, Lisa; Moll, Stephan; Rooney, Mary R; Cushman, Mary; Zakai, Neil A

2018-03-01

 Warfarin and direct oral anticoagulants (DOACs) are used for the initial treatment and secondary prevention of venous thromboembolism (VTE), and have similar efficacy. Patient concerns and preferences are important considerations when selecting an anticoagulant, yet these are not well studied.  VTE patients ( n  = 519) were surveyed from online sources (clotconnect.org, stoptheclot.org and National Blood Clot Alliance Facebook followers [ n  = 495]) and a haematology clinic in Vermont ( n  = 24).  Patients were 83% females and on average (±standard deviation [SD]) 45.7 ± 13.1 years; 65% self-reported warfarin as their initial VTE treatment and 35% a DOAC. Proportions reporting being extremely concerned about the following outcomes were as follows: recurrent VTE 33%, major bleeding 21%, moderate bleeding 16% and all-cause death 29%. When asked about oral anticoagulant characteristics, patients strongly preferred anticoagulants that are reversible (53%), and for which blood drug levels can be monitored (30%). Lower proportions agreed with statements that regular blood testing is inconvenient (18%), that they are comfortable using the newest drug versus an established drug (15%) and that it is difficult to change their diet to accommodate their anticoagulant (17%). In multivariable-adjusted models, patients tended to have had as their initial treatment, and to currently be taking, the oral anticoagulant option they personally preferred.  Patients held the greatest concern for recurrent VTE and mortality, regardless of which treatment they were prescribed. Potential weaknesses of warfarin (e.g., dietary restrictions, regular monitoring) were generally not considered onerous, while warfarin's advantages (e.g., ability to monitor) were viewed favourably. Schattauer GmbH Stuttgart.

Evaluating the efficacy of citrate anticoagulation during CRRT in cardiac patients

Directory of Open Access Journals (Sweden)

А. М. Караськов

2015-10-01

Full Text Available Systemic anticoagulation during renal replacement therapy in cardiac patients increases the risk of postoperative complications. Citrate anticoagulation is a promising alternative. The objective of our study was to evaluate the efficacy of citrate anticoagulation and its influence on the parameters of hemostasis and complications.

Cell wall O-glycoproteins and N-glycoproteins: biosynthesis and some functional aspects.

Directory of Open Access Journals (Sweden)

Eric eNguema-Ona

2014-10-01

Full Text Available Cell wall O-glycoproteins and N-glycoproteins are two types of glycomolecules whose glycans are structurally complex. They are both assembled and modified within the endomembrane system, i.e., the endoplasmic reticulum (ER and the Golgi apparatus, before their transport to their final locations within or outside the cell. In contrast to extensin, the O-glycan chains of arabinogalactan proteins are highly heterogeneous consisting mostly of (i a short oligo-arabinoside chain of three to four residues, and (ii a larger -1,3-linked galactan backbone with -1,6-linked side chains containing galactose, arabinose and, often, fucose, rhamnose or glucuronic acid. The fine structure of arabinogalactan chains varies between, and within plant species, and is important for the functional activities of the glycoproteins. With regards to N-glycans, ER-synthesizing events are highly conserved in all eukaryotes studied so far since they are essential for efficient protein folding. In contrast, evolutionary adaptation of N-glycan processing in the Golgi apparatus has given rise to a variety of organism-specific complex structures. Therefore, plant complex-type N-glycans contain specific glyco-epitopes such as core 1,2-xylose, core 1,3-fucose residues and Lewisa substitutions on the terminal position of the antenna. Like O-glycans, N-glycans of proteins are essential for their stability and function. Mutants affected in the glycan metabolic pathways have provided valuable information on the role of N-/O-glycoproteins in the control of growth, morphogenesis and adaptation to biotic and abiotic stresses. With regards to O-glycoproteins only extensin and arabinogalactan proteins are considered herein. The biosynthesis of these glycoproteins and functional aspects are presented and discussed in this review.

Idarucizumab for Reversing Dabigatran-Induced Anticoagulation: A Systematic Review.

Science.gov (United States)

Thibault, Nathan; Morrill, Amanda M; Willett, Kristine C

The approval of the oral direct thrombin inhibitor, dabigatran etexilate, gave patients an alternative to oral anticoagulation with warfarin. Like all anticoagulants, the primary adverse event (AE) associated with dabigatran is bleeding. Until the FDA approval of idarucizumab, there had been no reversal agent for dabigatran-induced anticoagulation in patients with life-threatening or uncontrollable bleeding, or those requiring emergent procedures. The primary purpose of this review is to summarize the safety and efficacy of idarucizumab, a monoclonal antibody fragment, and its use as a reversal agent for dabigatran. A literature search was conducted through MEDLINE (1946 to November week 1 2015) and Embase (1980-2015 week 46) using the search term idarucizumab. Clinicaltrials.gov was consulted for a comprehensive list of ongoing and completed studies. Additional studies were identified through bibliographical citations. Clinical trials in animals and humans published in English evaluating the safety and efficacy of idarucizumab for reversal of anticoagulant treatment with dabigatran were included for review. Idarucizumab has been shown to significantly reverse the anticoagulant effects of dabigatran in both healthy volunteers and patients requiring a reversal agent because of either overt bleeding or an emergency surgery or invasive procedure. The most common AEs were headache, nasopharyngitis, back pain, skin irritation, hypokalemia, delirium, constipation, pyrexia, and pneumonia. Deaths reported in idarucizumab studies were attributed to either the index event or a preexisting comorbidity. Most adverse effects were minor, but 21 serious AEs have been reported in the published data including thrombotic events. Given the increased use of direct oral anticoagulants, such as dabigatran, a need for specific reversal agents exists. Idarucizumab has been shown to be safe and effective in the reversal of dabigatran-induced anticoagulation in patients requiring emergent

[The study of anticoagulants selection in platelet-rich plasma preparation].

Science.gov (United States)

Hua, Lei; Lai, Gui; Zhenjun, Liu; Guie, Ma

2015-07-01

To investigate the effect of the anticoagulants on PRP quality, so as to clarify the appropriate anticoagulant used in PRP production. The microstructure change of platelets collected via heparin, citrate, acid citrate dextrose (ACD) and citrate-theophylline-adenosine-dipyridamole ( CTAD) was observed by TEM following time course. The extent of spontaneous activation of platelets in four groups was detected by measuring sP-selectin in plasma. The TGF-β1 release amount of activated PRP of four groups was measured. CTAD is superior to other anticoagulants in maintaining the integrity of platelet structures for a long time and preventing platelet spontaneous activation. ACD slightly surpassed heparin and citrate in above two aspects. ACD-PRP and CTAD-PRP released significantly more TGF-β1 compared with heparin and citrate. The PRP quality and biological effects were strongly associated with the type of Anticoagulants. ACD and CTAD are optimal anticoagulants in PRP production for they can maintain platelet viability at a high level.

Characterization of the disassembly and reassembly of the HBV glycoprotein surface antigen, a pliable nanoparticle vaccine platform

International Nuclear Information System (INIS)

Gallagher, John R.; Torian, Udana; McCraw, Dustin M.; Harris, Audray K.

2017-01-01

While nanoparticle vaccine technology is gaining interest due to the success of vaccines like those for the human papillomavirus that is based on viral capsid nanoparticles, little information is available on the disassembly and reassembly of viral surface glycoprotein-based nanoparticles. One such particle is the hepatitis B virus surface antigen (sAg) that exists as nanoparticles. Here we show, using biochemical analysis coupled with electron microscopy, that sAg nanoparticle disassembly requires both reducing agent to disrupt intermolecular disulfide bonds, and detergent to disrupt hydrophobic interactions that stabilize the nanoparticle. Particles were otherwise resistant to salt and urea, suggesting the driving mechanism of particle formation involves hydrophobic interactions. We reassembled isolated sAg protein into nanoparticles by detergent removal and reassembly resulted in a wider distribution of particle diameters. Knowledge of these driving forces of nanoparticle assembly and stability should facilitate construction of epitope-displaying nanoparticles that can be used as immunogens in vaccines.

Characterization of the disassembly and reassembly of the HBV glycoprotein surface antigen, a pliable nanoparticle vaccine platform

Energy Technology Data Exchange (ETDEWEB)

Gallagher, John R.; Torian, Udana; McCraw, Dustin M.; Harris, Audray K., E-mail: harrisau@mail.nih.gov

2017-02-15

While nanoparticle vaccine technology is gaining interest due to the success of vaccines like those for the human papillomavirus that is based on viral capsid nanoparticles, little information is available on the disassembly and reassembly of viral surface glycoprotein-based nanoparticles. One such particle is the hepatitis B virus surface antigen (sAg) that exists as nanoparticles. Here we show, using biochemical analysis coupled with electron microscopy, that sAg nanoparticle disassembly requires both reducing agent to disrupt intermolecular disulfide bonds, and detergent to disrupt hydrophobic interactions that stabilize the nanoparticle. Particles were otherwise resistant to salt and urea, suggesting the driving mechanism of particle formation involves hydrophobic interactions. We reassembled isolated sAg protein into nanoparticles by detergent removal and reassembly resulted in a wider distribution of particle diameters. Knowledge of these driving forces of nanoparticle assembly and stability should facilitate construction of epitope-displaying nanoparticles that can be used as immunogens in vaccines.

New oral anticoagulant-induced bleeding: clinical presentation and management

NARCIS (Netherlands)

Levy, Jerrold H.; Levi, Marcel

2014-01-01

Bleeding is a significant complication of anticoagulant therapy. With the emergence of new oral anticoagulants (NOACs; ie, direct factor IIa or Xa inhibitors), this risk is further compounded by the lack of validated reversal strategies for these agents. Emerging postmarketing evidence suggests that

A hybrid monolithic column based on boronate-functionalized graphene oxide nanosheets for online specific enrichment of glycoproteins.

Science.gov (United States)

Zhou, Chanyuan; Chen, Xiaoman; Du, Zhuo; Li, Gongke; Xiao, Xiaohua; Cai, Zongwei

2017-05-19

A hybrid monolithic column based on aminophenylboronic acid (APBA)-functionalized graphene oxide (GO) has been developed and used for selective enrichment of glycoproteins. The APBA/GO composites were homogeneously incorporated into a polymer monolithic column with the help of oligomer matrix and followed by in situ polymerization. The effect of dispersion of APBA/GO composites in the polymerization mixture on the performance of the monolithic column was explored in detail. The presence of graphene oxide not only enlarged the BET surface area from 6.3m 2 /g to 169.4m 2 /g, but also provided abundant boronic acid moieties for glycoprotein extraction, which improved the enrichment selectivity and efficiency for glycoproteins. The APBA/GO hybrid monolithic column was incorporated into a sequential injection system, which facilitated online extraction of proteins. Combining the superior properties of extraordinary surface area of GO and the affinity interaction of APBA to glycoproteins, the APBA/GO hybrid monolithic column showed higher enrichment factors for glycoproteins than other proteins without cis-diol-containing groups. Also, under comparable or even shorter processing time and without the addition of any organic solvent, it showed higher binding capacity toward glycoproteins compared with the conventional boronate affinity monolithic column. The practical applicability of this system was demonstrated by processing of egg white samples for extraction of ovalbumin and ovotransferrin, and satisfactory results were obtained by assay with SDS-PAGE. Copyright © 2017 Elsevier B.V. All rights reserved.

Disadvantages of VKA and requirements for novel anticoagulants.

Science.gov (United States)

Shameem, Raji; Ansell, Jack

2013-06-01

Vitamin K antagonists have been in wide use for over 70 years. Warfarin, the most commonly used vitamin K antagonist, has been shown to be highly effective in treating and preventing thrombosis. Despite this, warfarin has many disadvantages, which has led to the development of a new class of oral anticoagulants targeted to specific coagulation factors designated as target-specific oral anticoagulants (TSOAs). TSOAs include the thrombin inhibitors (dabigatran) and factor Xa inhibitors (rivaroxaban, apixaban). This chapter reviews the disadvantages of warfarin and evaluates both the advantages and disadvantages of the new oral anticoagulants. © 2013 Elsevier Ltd. All rights reserved.

Hematometra secondary to anticoagulant rodenticide toxicity

International Nuclear Information System (INIS)

Padgett, S.L.; Stokes, J.E.; Tucker, R.L.; Wheaton, L.G.

1998-01-01

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

Standards of care issues with anticoagulation in real-world populations.

Science.gov (United States)

2015-01-01

Current guidelines recommend anticoagulants for reducing the risk of stroke in appropriate patients with nonvalvular atrial fibrillation (NVAF) and for the acute treatment of venous thromboembolism (VTE) and the prevention of recurrent VTE. Warfarin is the standard of care for both NVAF and VTE, yet International Normalized Ratio (INR) control remains suboptimal, even in the clinical trial setting. Maintaining INR within the recommended therapeutic range is associated with better outcomes in these distinct populations. In VTE, high rates of recurrence have been reported during the first few weeks of treatment, emphasizing the importance of surveillance during this time and of early optimization of anticoagulation therapy. The NVAF population tends to have more comorbidities and requires longer-term therapy. It is important to keep in mind that real-world patient populations are more complex than those in controlled studies. Patients with multiple comorbidities are particularly challenging, and physicians may focus on clinically urgent issues rather than anticoagulation optimization. Despite the many complexities associated with the use of warfarin, it remains a mainstay of anticoagulation therapy. Aligning financial incentives and improving care coordination are important factors in moving toward better outcomes for patients who need anticoagulation therapy. The increased focus on value-based care and evolving approaches to patient treatment could lead more physicians and payers to consider alternatives to warfarin, including the use of novel oral anticoagulants.

Enhancement of Ebola Virus Infection via Ficolin-1 Interaction with the Mucin Domain of GP Glycoprotein.

Science.gov (United States)

Favier, Anne-Laure; Gout, Evelyne; Reynard, Olivier; Ferraris, Olivier; Kleman, Jean-Philippe; Volchkov, Viktor; Peyrefitte, Christophe; Thielens, Nicole M

2016-06-01

Ebola virus infection requires the surface viral glycoprotein to initiate entry into the target cells. The trimeric glycoprotein is a highly glycosylated viral protein which has been shown to interact with host C-type lectin receptors and the soluble complement recognition protein mannose-binding lectin, thereby enhancing viral infection. Similarly to mannose-binding lectin, ficolins are soluble effectors of the innate immune system that recognize particular glycans at the pathogen surface. In this study, we demonstrate that ficolin-1 interacts with the Zaire Ebola virus (EBOV) glycoprotein, and we characterized this interaction by surface plasmon resonance spectroscopy. Ficolin-1 was shown to bind to the viral glycoprotein with a high affinity. This interaction was mediated by the fibrinogen-like recognition domain of ficolin-1 and the mucin-like domain of the viral glycoprotein. Using a ficolin-1 control mutant devoid of sialic acid-binding capacity, we identified sialylated moieties of the mucin domain to be potential ligands on the glycoprotein. In cell culture, using both pseudotyped viruses and EBOV, ficolin-1 was shown to enhance EBOV infection independently of the serum complement. We also observed that ficolin-1 enhanced EBOV infection on human monocyte-derived macrophages, described to be major viral target cells,. Competition experiments suggested that although ficolin-1 and mannose-binding lectin recognized different carbohydrate moieties on the EBOV glycoprotein, the observed enhancement of the infection likely depended on a common cellular receptor/partner. In conclusion, ficolin-1 could provide an alternative receptor-mediated mechanism for enhancing EBOV infection, thereby contributing to viral subversion of the host innate immune system. A specific interaction involving ficolin-1 (M-ficolin), a soluble effector of the innate immune response, and the glycoprotein (GP) of EBOV was identified. Ficolin-1 enhanced virus infection instead of tipping the

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

DEFF Research Database (Denmark)

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

2003-01-01

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

Palmitoylation of the cysteine-rich endodomain of the SARS-coronavirus spike glycoprotein is important for spike-mediated cell fusion

International Nuclear Information System (INIS)

Petit, Chad M.; Chouljenko, Vladimir N.; Iyer, Arun; Colgrove, Robin; Farzan, Michael; Knipe, David M.; Kousoulas, K.G.

2007-01-01

The SARS-coronavirus (SARS-CoV) is the etiological agent of the severe acute respiratory syndrome (SARS). The SARS-CoV spike (S) glycoprotein mediates membrane fusion events during virus entry and virus-induced cell-to-cell fusion. The cytoplasmic portion of the S glycoprotein contains four cysteine-rich amino acid clusters. Individual cysteine clusters were altered via cysteine-to-alanine amino acid replacement and the modified S glycoproteins were tested for their transport to cell-surfaces and ability to cause cell fusion in transient transfection assays. Mutagenesis of the cysteine cluster I, located immediately proximal to the predicted transmembrane, domain did not appreciably reduce cell-surface expression, although S-mediated cell fusion was reduced by more than 50% in comparison to the wild-type S. Similarly, mutagenesis of the cysteine cluster II located adjacent to cluster I reduced S-mediated cell fusion by more than 60% compared to the wild-type S, while cell-surface expression was reduced by less than 20%. Mutagenesis of cysteine clusters III and IV did not appreciably affect S cell-surface expression or S-mediated cell fusion. The wild-type S was palmitoylated as evidenced by the efficient incorporation of 3 H-palmitic acid in wild-type S molecules. S glycoprotein palmitoylation was significantly reduced for mutant glycoproteins having cluster I and II cysteine changes, but was largely unaffected for cysteine cluster III and IV mutants. These results show that the S cytoplasmic domain is palmitoylated and that palmitoylation of the membrane proximal cysteine clusters I and II may be important for S-mediated cell fusion

New anticoagulants for the prevention and treatment of venous thromboembolism

Directory of Open Access Journals (Sweden)

Simon J McRae

2005-04-01

Full Text Available Simon J McRae, Jeffrey S GinsbergDepartment of Medicine, McMaster University, Hamilton, ON, CanadaAbstract: Anticoagulant therapy is effective at preventing the development of venous thromboembolism in high-risk patients, and reduces morbidity and mortality in individuals with established thromboembolic disease. Vitamin K antagonists and heparins are currently the most commonly used anticoagulant drugs, but they have practical limitations. Therefore, new antithrombotic agents with predictable dose-responses (thereby decreasing the need for monitoring without compromising efficacy or safety, ideally available in an oral formulation and with a rapidly reversible anticoagulant effect, are needed. New drugs fulfilling some of the above criteria have been developed and have proven to be effective agents for the treatment and prevention of venous thromboembolism.Keywords: venous thromboembolism, anticoagulants, antithrombotic

Glycoprotein biosynthesis by human normal platelets

International Nuclear Information System (INIS)

Rodriguez, P.; Bello, O.; Apitz-Castro, R.

1987-01-01

Incorporation of radioactive Man, Gal, Fuc, Glc-N, and NANA into washed human normal platelets and endogenous glycoproteins has been found. Both parameters were time dependent. Analysis of hydrolyzed labeled glycoproteins by paper chromatography revealed that the radioactive monosaccharide incubated with the platelets had not been converted into other sugars. Acid hydrolysis demonstrates the presence of a glycosidic linkage. All the effort directed to the demonstration of the existence of a lipid-sugar intermediate in intact human platelets yielded negative results for Man and Glc-N used as precursors. The incorporation of these sugars into glycoproteins is insensitive to bacitracin, suggesting no involvement of lipid-linked saccharides in the synthesis of glycoproteins in human blood platelets. The absence of inhibition of the glycosylation process in the presence of cycloheximide suggests that the sugars are added to proteins present in the intact platelets. These results support the contention that glycoprotein biosynthesis in human blood platelets observed under our experimental conditions is effected through direct sugar nucleotide glycosylation

Adherence to a new oral anticoagulant treatment prescription: dabigatran etexilate

Directory of Open Access Journals (Sweden)

L Bellamy

2009-07-01

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

Scoring Systems for Estimating the Risk of Anticoagulant-Associated Bleeding.

Science.gov (United States)

Parks, Anna L; Fang, Margaret C

2017-07-01

Anticoagulant medications are frequently used to prevent and treat thromboembolic disease. However, the benefits of anticoagulants must be balanced with a careful assessment of the risk of bleeding complications that can ensue from their use. Several bleeding risk scores are available, including the Outpatient Bleeding Risk Index, HAS-BLED, ATRIA, and HEMORR 2 HAGES risk assessment tools, and can be used to help estimate patients' risk for bleeding on anticoagulants. These tools vary by their individual risk components and in how they define and weigh clinical factors. However, it is not yet clear how best to integrate bleeding risk tools into clinical practice. Current bleeding risk scores generally have modest predictive ability and limited ability to predict the most devastating complication of anticoagulation, intracranial hemorrhage. In clinical practice, bleeding risk tools should be paired with a formal determination of thrombosis risk, as their results may be most influential for patients at the lower end of thrombosis risk, as well as for highlighting potentially modifiable risk factors for bleeding. Use of bleeding risk scores may assist clinicians and patients in making informed and individualized anticoagulation decisions. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

N-terminal sequence of human leukocyte glycoprotein Mo1: conservation across species and homology to platelet IIb/IIIa.

Science.gov (United States)

Pierce, M W; Remold-O'Donnell, E; Todd, R F; Arnaout, M A

1986-12-12

Mo1 and gp160-gp93 are two surface membrane glycoprotein heterodimers present on granulocytes and monocytes derived from humans and guinea pigs, respectively. We purified both antigens and found that their alpha subunits had identical N-termini which were significantly homologous to the alpha subunit of the human adhesion platelet glycoprotein IIb/IIIa.

Atrial Fibrillation in Embolic Stroke: Anticoagulant Therapy at UNTH ...

African Journals Online (AJOL)

Objective: The decision to commence anticoagulation in a patient with embolic stroke and atrial fibrillation (AF) is often a difficult one for many clinicians. The result can have significant impact on the patient. This study was therefore undertaken to review the use of anticoagulation in embolic stroke in the setting of atrial ...

Bleeding events associated with novel anticoagulants: a case series.

Science.gov (United States)

Mirzaee, Sam; Tran, Tara Thi Thien; Amerena, John

2013-12-01

Until lately warfarin was the only valuable oral anticoagulant in stroke reduction in high risk cases with non valvular atrial fibrillation (NVAF). Although with warfarin the rate of stroke reduced notably, the major concern is the risk of serious bleeding and difficulty of establishing and maintaining the international normalised ratio (INR) within the therapeutic range. With the development of the novel anticoagulants we now have for the first time since the innovation of Warfarin feasible alternatives to it to decrease stroke rates in high risk patients with NVAF. To diminish adverse bleeding events with the novel anticoagulant proper selection of patients prior starting treatment is essential. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Relationship between heparin anticoagulation and clinical outcomes in coronary stent intervention: observations from the ESPRIT trial.

Science.gov (United States)

Tolleson, Thaddeus R; O'Shea, J Conor; Bittl, John A; Hillegass, William B; Williams, Kathryn A; Levine, Glenn; Harrington, Robert A; Tcheng, James E

2003-02-05

We evaluated the relationship between the degree of heparin anticoagulation and clinical efficacy and bleeding in patients undergoing contemporary percutaneous coronary intervention (PCI) with stent implantation. Despite universal acceptance of heparin anticoagulation as a standard of care in PCI, considerable controversy still exists regarding the appropriate dosing of heparin. The study population (n = 2,064) comprised all patients enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial. The index activated clotting time (ACT) was defined as the ACT measured after the last heparin dose and before first device activation and was correlated with outcome and bleeding events. No association was observed between decreasing ACT levels and the rate of ischemic events in the treatment or placebo arms. The incidence of the primary composite end point (death, myocardial infarction, urgent target vessel revascularization, and thrombotic bailout glycoprotein IIb/IIIa inhibitor therapy at 48 h) was actually lowest in the lowest ACT tertile for both the placebo (10.0%) and treatment groups (6.1%). When analyzed by tertile, major bleeding rates did not increase in the lowest ACT tertile in patients given placebo (0.6%) versus those receiving eptifibatide (0.7%). Major bleeding rates increased as the ACT increased in the eptifibatide-treated patients. Ischemic end points in patients undergoing contemporary PCI with stent placement do not increase by decreasing ACT levels, at least to a level of 200 s. Bleeding events do increase with increasing ACT levels and are enhanced with eptifibatide treatment. An ACT of 200 to 250 s is reasonable in terms of efficacy and safety with the use of contemporary technology and pharmacotherapy.

Synthesis and biological activity of the novel indanedione anticoagulant rodenticides containing fluorine.

Science.gov (United States)

Chen, Feng; Liu, Liping; Bai, Zengguo; Zhang, Tianhua; Zhao, Keke

2017-01-02

Here, 3 fluorinated intermediates of drug were synthesized: (M1), (M2), (M3). Three new anticoagulant rodenticides were designed which were based on 4-hydroxycoumarin or 1,3-indandione, added acute toxicity groups containing fluorine. The structures of synthesized compounds were analyzed and proved by FT-IR spectroscopy and 1 H nuclear magnetic resonance ( 1 H-NMR). The compounds were also evaluated for their anticoagulant and acute biologic activity. In addition, both the acute orally toxicity and the feeding indexes of R 1 and R 2 were tested. The result of the experiment proved that the new synthesis of 1, 3 - indan diketone for maternal new anticoagulant rodenticide can replace the current 4 - hydroxyl coumarin as the mother of the second generation anticoagulant rodenticide and 1, 3 - indan diketone for maternal new anticoagulant rodenticides will have a good development prospect.

Bleeding in patients using new anticoagulants or antiplatelet agents: Risk factors and management

NARCIS (Netherlands)

Levi, M.M.; Eerenberg, E.; Löwenberg, E.; Kamphuisen, P.W.

2010-01-01

The most important adverse effect of antithrombotic treatment is the occurrence of bleeding. in case of serious or even life-threatening bleeding in a patient who uses anticoagulant agents or when patient on anticoagulants needs to undergo an urgent invasive procedure, anticoagulant treatment can be

Anticoagulant rodenticides and wildlife: Introduction

Science.gov (United States)

van den Brink, Nico W.; Elliott, John E.; Shore, Richard F.; Rattner, Barnett A.; van den Brink, Nico W.; Elliott, John E.; Shore, Richard F.; Rattner, Barnett A.

2018-01-01

Rodents have interacted with people since the beginning of systematic food storage by humans in the early Neolithic era. Such interactions have had adverse outcomes such as threats to human health, spoiling and consumption of food sources, damage to human infrastructure and detrimental effects on indigenous island wildlife (through inadvertent anthropogenic assisted introductions). These socio/economic and environmental impacts illustrate the clear need to control populations of commensal rodents. Different methods have been applied historically but the main means of control in the last decades is through the application of rodenticides, mainly anticoagulant rodenticides (ARs) that inhibit blood clotting. The so-called First Generation Anticoagulant Rodenticides (FGARs) proved highly effective but rodents increasingly developed resistance. This led to a demand for more effective alternative compounds and paved the way to the development of Second Generation Anticoagulant Rodenticides (SGARs). These were more acutely toxic and persistent, making them more effective but also increasing the risks of exposure of non-target species and secondary poisoning of predatory species. SGARs often fail the environmental thresholds of different regulatory frameworks because of these negative side-effects, but their use is still permitted because of the overwhelming societal needs for rodent control and the lack of effective alternatives. This book provides a state-of-the-art overview of the scientific advancements in assessment of environmental exposure, effects and risks of currently used ARs. This is discussed in relation to the societal needs for rodent control, including risk mitigation and development of alternatives.

Podoplanin - a small glycoprotein with many faces

OpenAIRE

Ugorski, Maciej; Dziegiel, Piotr; Suchanski, Jaroslaw

2016-01-01

Podoplanin is a small membrane glycoprotein with a large number of O-glycoside chains and therefore it belongs to mucin-type proteins. It can be found on the surface of many types of normal cells originating from various germ layers. It is present primarily on the endothelium of lymphatic vessels, type I pneumocytes and glomerular podocytes. Increased levels of podoplanin or its neo-expression have been found in numerous types of human carcinomas, but it is especially common in squamous cell ...

The effect of the amiodarone-warfarin interaction on anticoagulation quality in a single, high-quality anticoagulation center.

Science.gov (United States)

White, Ryan D; Riggs, Kyle W; Ege, Ed J; Petroski, Gregory F; Koerber, Scott M; Flaker, Greg

2016-03-01

Clinical trials have reported a low time in therapeutic range (TTR) in patients with atrial fibrillation treated with both warfarin andamiodarone. These trials included centers and countries with both high and low TTRs. What is the impact of amiodarone on the TTR in a single, high-quality anticoagulation clinic? TTR was assessed in amiodarone and nonamiodarone-treated patients from a University anticoagulation clinic. Baseline characteristics between patients ever-taking or never-taking amiodarone were similar, except more amiodarone patients were smokers (19.5 vs. 6.1%, P = 0.0031). The TTR calculated from 8901international normalized ratios (INRs) in 249 nonamiodarone patients with a mean follow-up of 34 ± 20 months (mean INR 36 ± 18) was 66 ± 16.6% compared with 61.3 ± 16.2% (P = 0.111) from 1455 INRs in 41 amiodarone-treated patients with a mean follow-up of 28 ± 20 months (mean INR 35 ± 22). Factors associated with a low TTR were male sex (P = 0.0013), smoker (P = 0.0048), and amiodarone use (P = 0.0374). A second on-treatment analysis, in which the TTR was calculated only during amiodarone therapy, resulted in similar findings; however, amiodarone did not emerge as a predictor of a low TTR. In 11 patients, the TTR prior to amiodarone (54.5 ± 22.2%) was not significantly different in the first 3 months (54.6 ± 33.4%) or after 3 months (67.2 ± 33.7%) of amiodarone. In a single high-quality anticoagulation center, anticoagulation quality, as measured by the TTR, can be comparable in amiodarone and nonamiodarone-treated patients.

Effect of an interactive voice response system on oral anticoagulant management.

Science.gov (United States)

Oake, Natalie; van Walraven, Carl; Rodger, Marc A; Forster, Alan J

2009-04-28

Monitoring oral anticoagulants is logistically challenging for both patients and medical staff. We evaluated the effect of adding an interactive voice response system to computerized decision support for oral anticoagulant management. We developed an interactive voice response system to communicate to patients the results of international normalized ratio testing and their dosage schedules for anticoagulation therapy. The system also reminded patients of upcoming and missed appointments for blood tests. We recruited patients whose anticoagulation control was stable after at least 3 months of warfarin therapy. We prospectively examined clinical data and outcomes for these patients for an intervention period of at least 3 months. We also collected retrospective data for each patient for the 3 months before study enrolment. We recruited 226 patients between Nov. 23, 2006, and Aug. 1, 2007. The mean duration of the intervention period (prospective data collection) was 4.2 months. Anticoagulation control was similar for the periods during and preceding the intervention (mean time within the therapeutic range 80.3%, 95% confidence interval [CI] 77.5% to 83.1% v. 79.9%, 95% CI 77.3% to 82.6%). The interactive voice response system delivered 1211 (77.8%) of 1557 scheduled dosage messages, with no further input required from clinic staff. The most common reason for clinic staff having to deliver the remaining messages (accounting for 143 [9.2%] of all messages) was an international normalized ratio that was excessively high or low, (i.e., 0.5 or more outside the therapeutic range). When given the option, 76.6% of patients (164/214) chose to continue with the interactive voice response system for management of their anticoagulation after the study was completed. The system reduced staff workload for monitoring anticoagulation therapy by 48 min/wk, a 33% reduction from the baseline of 2.4 hours. Interactive voice response systems have a potential role in improving the

Reproductive success of bromadiolone-resistant rats in absence of anticoagulant pressure

DEFF Research Database (Denmark)

Heiberg, Ann-Charlotte; Leirs, Herwig; Siegismund, Hans Redlef

2006-01-01

Resistance to anticoagulant rodenticides in brown rats (Rattus norvegicus Berk.) is associated with pleiotropic effects, notably with an increased dietary vitamin K requirement. Owing to this disadvantage, resistance is believed to be selected against if anticoagulant selection is absent. In small...... experimental populations of wild brown rats, an investigation was carried out to establish whether tolerance to anticoagulant exposure changed over a period of 2 years. In the same populations, DNA microsatellite markers were used to infer parentage, and this made it possible to estimate reproductive success...... of sensitive and resistant rats and estimate effective population size, Ne. Even though there was evidence for a selection against resistant rats with high vitamin K requirement, anticoagulant tolerance was not seen to be significantly influenced in the absence of bromadiolone selection. As the population size...

Statins Suppress Ebola Virus Infectivity by Interfering with Glycoprotein Processing.

Science.gov (United States)

Shrivastava-Ranjan, Punya; Flint, Mike; Bergeron, Éric; McElroy, Anita K; Chatterjee, Payel; Albariño, César G; Nichol, Stuart T; Spiropoulou, Christina F

2018-05-01

Ebola virus (EBOV) infection is a major public health concern due to high fatality rates and limited effective treatments. Statins, widely used cholesterol-lowering drugs, have pleiotropic mechanisms of action and were suggested as potential adjunct therapy for Ebola virus disease (EVD) during the 2013-2016 outbreak in West Africa. Here, we evaluated the antiviral effects of statin (lovastatin) on EBOV infection in vitro Statin treatment decreased infectious EBOV production in primary human monocyte-derived macrophages and in the hepatic cell line Huh7. Statin treatment did not interfere with viral entry, but the viral particles released from treated cells showed reduced infectivity due to inhibition of viral glycoprotein processing, as evidenced by decreased ratios of the mature glycoprotein form to precursor form. Statin-induced inhibition of infectious virus production and glycoprotein processing was reversed by exogenous mevalonate, the rate-limiting product of the cholesterol biosynthesis pathway, but not by low-density lipoprotein. Finally, statin-treated cells produced EBOV particles devoid of the surface glycoproteins required for virus infectivity. Our findings demonstrate that statin treatment inhibits EBOV infection and suggest that the efficacy of statin treatment should be evaluated in appropriate animal models of EVD. IMPORTANCE Treatments targeting Ebola virus disease (EVD) are experimental, expensive, and scarce. Statins are inexpensive generic drugs that have been used for many years for the treatment of hypercholesterolemia and have a favorable safety profile. Here, we show the antiviral effects of statins on infectious Ebola virus (EBOV) production. Our study reveals a novel molecular mechanism in which statin regulates EBOV particle infectivity by preventing glycoprotein processing and incorporation into virus particles. Additionally, statins have anti-inflammatory and immunomodulatory effects. Since inflammation and dysregulation of the immune

eEF-2 Phosphorylation Down-Regulates P-Glycoprotein Over-Expression in Rat Brain Microvessel Endothelial Cells.

Directory of Open Access Journals (Sweden)

Xing Hua Tang

Full Text Available We investigated whether glutamate, NMDA receptors, and eukaryote elongation factor-2 kinase (eEF-2K/eEF-2 regulate P-glycoprotein expression, and the effects of the eEF-2K inhibitor NH125 on the expression of P-glycoprotein in rat brain microvessel endothelial cells (RBMECs.Cortex was obtained from newborn Wistar rat brains. After surface vessels and meninges were removed, the pellet containing microvessels was resuspended and incubated at 37°C in culture medium. Cell viability was assessed by the MTT assay. RBMECs were identified by immunohistochemistry with anti-vWF. P-glycoprotein, phospho-eEF-2, and eEF-2 expression were determined by western blot analysis. Mdr1a gene expression was analyzed by RT-PCR.Mdr1a mRNA, P-glycoprotein and phospho-eEF-2 expression increased in L-glutamate stimulated RBMECs. P-glycoprotein and phospho-eEF-2 expression were down-regulated after NH125 treatment in L-glutamate stimulated RBMECs.eEF-2K/eEF-2 should have played an important role in the regulation of P-glycoprotein expression in RBMECs. eEF-2K inhibitor NH125 could serve as an efficacious anti-multidrug resistant agent.

Developing an Anti-Xa-Based Anticoagulation Protocol for Patients with Percutaneous Ventricular Assist Devices.

Science.gov (United States)

Sieg, Adam; Mardis, B Andrew; Mardis, Caitlin R; Huber, Michelle R; New, James P; Meadows, Holly B; Cook, Jennifer L; Toole, J Matthew; Uber, Walter E

2015-01-01

Because of the complexities associated with anticoagulation in temporary percutaneous ventricular assist device (pVAD) recipients, a lack of standardization exists in their management. This retrospective analysis evaluates current anticoagulation practices at a single center with the aim of identifying an optimal anticoagulation strategy and protocol. Patients were divided into two cohorts based on pVAD implanted (CentriMag (Thoratec; Pleasanton, CA) / TandemHeart (CardiacAssist; Pittsburgh, PA) or Impella (Abiomed, Danvers, MA)), with each group individually analyzed for bleeding and thrombotic complications. Patients in the CentriMag/TandemHeart cohort were subdivided based on the anticoagulation monitoring strategy (activated partial thromboplastin time (aPTT) or antifactor Xa unfractionated heparin (anti-Xa) values). In the CentriMag/TandemHeart cohort, there were five patients with anticoagulation titrated based on anti-Xa values; one patient developed a device thrombosis and a major bleed, whereas another patient experienced major bleeding. Eight patients received an Impella pVAD. Seven total major bleeds in three patients and no thrombotic events were detected. Based on distinct differences between the devices, anti-Xa values, and outcomes, two protocols were created to guide anticoagulation adjustments. However, anticoagulation in patients who require pVAD support is complex with constantly evolving anticoagulation goals. The ideal level of anticoagulation should be individually determined using several coagulation laboratory parameters in concert with hemodynamic changes in the patient's clinical status, the device, and the device cannulation.

Utilization of oral anticoagulation in a teaching hospital in Nigeria ...

African Journals Online (AJOL)

The mean age of the patients was 53.4 years and more females than males were on anticoagulation and monitoring (F14:M12). The most common indications for anticoagulation include deep venous thrombosis/pulmonary embolism, congestive heart failure with atrial fibrillation and mitral valve disease with atrial fibrillation.

Non-vitamin K antagonist oral anticoagulation agents in anticoagulant naïve atrial fibrillation patients

DEFF Research Database (Denmark)

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

2015-01-01

AIMS: Non-vitamin K antagonist oral anticoagulation (NOAC) agents have been approved for stroke prophylaxis in atrial fibrillation (AF). We investigated 'real-world' information on how these drugs are being adopted. METHODS AND RESULTS: Using Danish nationwide administrative registers, we identif...

Ammonia transport in the kidney by Rhesus glycoproteins

Science.gov (United States)

Verlander, Jill W.

2014-01-01

Renal ammonia metabolism is a fundamental element of acid-base homeostasis, comprising a major component of both basal and physiologically altered renal net acid excretion. Over the past several years, a fundamental change in our understanding of the mechanisms of renal epithelial cell ammonia transport has occurred, replacing the previous model which was based upon diffusion equilibrium for NH3 and trapping of NH4+ with a new model in which specific and regulated transport of both NH3 and NH4+ across renal epithelial cell membranes via specific membrane proteins is required for normal ammonia metabolism. A major advance has been the recognition that members of a recently recognized transporter family, the Rhesus glycoprotein family, mediate critical roles in renal and extrarenal ammonia transport. The erythroid-specific Rhesus glycoprotein, Rh A Glycoprotein (Rhag), was the first Rhesus glycoprotein recognized as an ammonia-specific transporter. Subsequently, the nonerythroid Rh glycoproteins, Rh B Glycoprotein (Rhbg) and Rh C Glycoprotein (Rhcg), were cloned and identified as ammonia transporters. They are expressed in specific cell populations and membrane domains in distal renal epithelial cells, where they facilitate ammonia secretion. In this review, we discuss the distribution of Rhbg and Rhcg in the kidney, the regulation of their expression and activity in physiological disturbances, the effects of genetic deletion on renal ammonia metabolism, and the molecular mechanisms of Rh glycoprotein-mediated ammonia transport. PMID:24647713

Hemorrhagic stroke and oral anticoagulants: What is to be done?

Directory of Open Access Journals (Sweden)

M. A. Domashenko

2016-01-01

Full Text Available Hemorrhagic stroke (HS is associated with high mortality and disability rates. Due to the introduction of the current guidelines for the prevention of systemic thromboembolic events in patients with atrial fibrillations and to an increase in the number of older patients, there has been a rise in the incidence of intracranial hemorrhage (ICH associated with the use of oral anticoagulants. The paper discusses medical treatment in patients with HS during therapy with vitamin K antagonists (warfarin and novel oral anticoagulants (dabigatran. rivaroxaban, apixaban, as well as an anticoagulant resumption policy after prior ICH in patients at high risk for thromboembolic events.

Nipah virus infection and glycoprotein targeting in endothelial cells

Directory of Open Access Journals (Sweden)

Maisner Andrea

2010-11-01

Full Text Available Abstract Background The highly pathogenic Nipah virus (NiV causes fatal respiratory and brain infections in animals and humans. The major hallmark of the infection is a systemic endothelial infection, predominantly in the CNS. Infection of brain endothelial cells allows the virus to overcome the blood-brain-barrier (BBB and to subsequently infect the brain parenchyma. However, the mechanisms of NiV replication in endothelial cells are poorly elucidated. We have shown recently that the bipolar or basolateral expression of the NiV surface glycoproteins F and G in polarized epithelial cell layers is involved in lateral virus spread via cell-to-cell fusion and that correct sorting depends on tyrosine-dependent targeting signals in the cytoplasmic tails of the glycoproteins. Since endothelial cells share many characteristics with epithelial cells in terms of polarization and protein sorting, we wanted to elucidate the role of the NiV glycoprotein targeting signals in endothelial cells. Results As observed in vivo, NiV infection of endothelial cells induced syncytia formation. The further finding that infection increased the transendothelial permeability supports the idea of spread of infection via cell-to-cell fusion and endothelial cell damage as a mechanism to overcome the BBB. We then revealed that both glycoproteins are expressed at lateral cell junctions (bipolar, not only in NiV-infected primary endothelial cells but also upon stable expression in immortalized endothelial cells. Interestingly, mutation of tyrosines 525 and 542/543 in the cytoplasmic tail of the F protein led to an apical redistribution of the protein in endothelial cells whereas tyrosine mutations in the G protein had no effect at all. This fully contrasts the previous results in epithelial cells where tyrosine 525 in the F, and tyrosines 28/29 in the G protein were required for correct targeting. Conclusion We conclude that the NiV glycoprotein distribution is responsible for

Anticoagulants Influence the Performance of In Vitro Assays Intended for Characterization of Nanotechnology-Based Formulations

Directory of Open Access Journals (Sweden)

Edward Cedrone

2017-12-01

Full Text Available The preclinical safety assessment of novel nanotechnology-based drug products frequently relies on in vitro assays, especially during the early stages of product development, due to the limited quantities of nanomaterials available for such studies. The majority of immunological tests require donor blood. To enable such tests one has to prevent the blood from coagulating, which is usually achieved by the addition of an anticoagulant into blood collection tubes. Heparin, ethylene diamine tetraacetic acid (EDTA, and citrate are the most commonly used anticoagulants. Novel anticoagulants such as hirudin are also available but are not broadly used. Despite the notion that certain anticoagulants may influence assay performance, a systematic comparison between traditional and novel anticoagulants in the in vitro assays intended for immunological characterization of nanotechnology-based formulations is currently not available. We compared hirudin-anticoagulated blood with its traditional counterparts in the standardized immunological assay cascade, and found that the type of anticoagulant did not influence the performance of the hemolysis assay. However, hirudin was more optimal for the complement activation and leukocyte proliferation assays, while traditional anticoagulants citrate and heparin were more appropriate for the coagulation and cytokine secretion assays. The results also suggest that traditional immunological controls such as lipopolysaccharide (LPS are not reliable for understanding the role of anticoagulant in the assay performance. We observed differences in the test results between hirudin and traditional anticoagulant-prepared blood for nanomaterials at the time when no such effects were seen with traditional controls. It is, therefore, important to recognize the advantages and limitations of each anticoagulant and consider individual nanoparticles on a case-by-case basis.

APPLICATIONS OF PHARMACOGENETIC TESTING FOR PERSONALIZATION OF THERAPY WITH ORAL ANTICOAGULANTS IN RUSSIA

Directory of Open Access Journals (Sweden)

D. A. Sychev

2013-01-01

Full Text Available The clinical significance of the patient genetic characteristics in the individual pharmacological response to oral anticoagulants is considered. Possible tactics of warfarin dosing and new oral anticoagulants choice on the basis of pharmacogenetic testing as well as indications for this approach in clinical practice are discussed. It should increase efficacy and safety of anticoagulant therapy.

[Research progress on ebola virus glycoprotein].

Science.gov (United States)

Ding, Guo-Yong; Wang, Zhi-Yu; Gao, Lu; Jiang, Bao-Fa

2013-03-01

Ebola virus (EBOV) causes outbreaks of a highly lethal hemorrhagic fever in humans and there are no effective therapeutic or prophylactic treatments available. The glycoprotein (GP) of EBOV is a transmembrane envelope protein known to play multiple functions including virus attachment and entry, cell rounding and cytotoxicity, down-regulation of host surface proteins, and enhancement of virus assembly and budding. GP is the primary target of protective immunity and the key target for developing neutralizing antibodies. In this paper, the research progress on genetic structure, pathogenesis and immunogenicity of EBOV GP in the last 5 years is reviewed.

Direct Oral Anticoagulants and Women

NARCIS (Netherlands)

Cohen, Hannah; Arachchillage, Deepa R. J.; Beyer-Westendorf, Jan; Middeldorp, Saskia; Kadir, Rezan A.

2016-01-01

Direct oral anticoagulants (DOACs) provide an effective, safe, and convenient therapeutic alternative to warfarin and other vitamin K antagonists (VKAs), and are now established for a wide range of indications. The use of DOACs in women merits special consideration due to two main situations: first,

The major surface glycoprotein (gp63) from Leishmania major and Leishmania donovani cleaves CD4 molecules on human T cells

DEFF Research Database (Denmark)

Hey, A S; Theander, T G; Hviid, L

1994-01-01

The effect of Leishmania major and L. donovani surface protease gp63 on surface markers on human T cells was studied using fluorescence-activated flow cytometry. Purified gp63 (63,000 m.w. glycoprotein) at concentrations above 10 micrograms/ml completely inhibited binding of six different anti-CD4......-expression of CD4, reaching 50% of the initial level after 72 h of incubation in medium. Preincubation of cells with live promastigotes showed an inhibitory effect on CD4 comparable to that seen with purified gp63. The binding of Abs directed against other surface markers present on human T-cells--CD2, CD3, CD5......, CD8, CD11A, CD25, CD45RO, CD45RA, CD58, TCR-alpha, TCR-gamma, and HLA DQ--was not inhibited by gp63. These data suggest that gp63, both in its purified form and in the form anchored to the parasite membrane, cleaves CD4 on human T cells. The cleavage of CD4 by the protease might play a role...

Anticoagulation Quality and Complications of using Vitamin K Antagonists in the Cardiac Surgery Outpatient Clinic

Directory of Open Access Journals (Sweden)

Mário Augusto Cray da Costa

Full Text Available ABSTRACT Introduction: In patients with mechanical prosthetic heart valves or atrial fibrillation requiring anticoagulation to prevent thromboembolic events, several factors influence adherence and anticoagulation complications. Objective: To evaluate the factors that interfere with the quality and complications of anticoagulation with vitamin K antagonists. Methods: A retrospective cohort study of 100 patients, in the period from 2011 to 2014, was performed. Anticoagulation conditions in the last year, regarding the presence of complications (embolisms/bleeding and inadequate treatment were assessed: achievement of less than 8 annual prothrombin times and International Normalized Ratio outside therapeutic target in more than 40% of prothrombin times. Results: There were 31 complications (22 minor bleeding without hospitalization and 9 major complications: 7 bleeding with hospitalization and two emboli; 70 were with International Normalized Ratio outside the target in more than 40% of the tests and 36 with insufficient number of prothrombin times. Socioeconomic factors, anticoagulant type and anticoagulation reason had no relationship with complications or with inadequate treatment. There were more complications in patients with longer duration of anticoagulation (P=0.001. Women had more International Normalized Ratio outside the target range (OR 2.61, CI:1.0-6.5; P=0.04. Patients with lower number of annual prothrombin times had longer times of anticoagulation (P=0.03, less annual consultations (P=0.02 and less dose adjustments (P=0.003. Patients with longer duration of anticoagulation have more complications (P=0.001. Conclusion: There was a high rate of major complications and International Normalized Ratio was outside the goal. Less annual prothrombin times was related to longer duration of anticoagulation, less annual consultations and less dose adjustments. More major complications occurred in patients with longer duration of

Glycan structures contain information for the spatial arrangement of glycoproteins in the plasma membrane.

Directory of Open Access Journals (Sweden)

M Kristen Hall

Full Text Available Glycoconjugates at the cell surface are crucial for cells to communicate with each other and the extracellular microenvironment. While it is generally accepted that glycans are vectorial biopolymers, their information content is unclear. This report provides evidence that distinct N-glycan structures influence the spatial arrangement of two integral membrane glycoproteins, Kv3.1 and E-cadherin, at the adherent membrane which in turn alter cellular properties. Distinct N-glycan structures were generated by heterologous expression of these glycoproteins in parental and glycosylation mutant Chinese hamster ovary cell lines. Unlike the N-linked glycans, the O-linked glycans of the mutant cell lines are similar to those of the parental cell line. Western and lectin blots of total membranes and GFP immunopurified samples, combined with glycosidase digestion reactions, were employed to verify the glycoproteins had predominantly complex, oligomannose, and bisecting type N-glycans from Pro(-5, Lec1, and Lec10B cell lines, respectively. Based on total internal reflection fluorescence and differential interference contrast microscopy techniques, and cellular assays of live parental and glycosylation mutant CHO cells, we propose that glycoproteins with complex, oligomannose or bisecting type N-glycans relay information for localization of glycoproteins to various regions of the plasma membrane in both a glycan-specific and protein-specific manner, and furthermore cell-cell interactions are required for deciphering much of this information. These distinct spatial arrangements also impact cell adhesion and migration. Our findings provide direct evidence that N-glycan structures of glycoproteins contribute significantly to the information content of cells.

Is stopping of anticoagulant therapy really required in a minor dental surgery? - How about in an endodontic microsurgery?

Directory of Open Access Journals (Sweden)

Yong-Wook Cho

2013-08-01

Full Text Available Nowadays, oral anticoagulants are commonly prescribed to numerous patients for preventing cardiovascular accident such as thromboembolism. An important side effect of anticoagulant is anti-hemostasis. In a major surgery, the oral anticoagulant therapy (OAT regimen must be changed before the surgery for proper post-operative bleeding control. However, in a minor dental surgery and endodontic surgery, the necessity for changing or discontinuing the OAT is open to debate. In this study, risks of the consequences were weighed and analyzed. In patients who stop the OAT, the occurrence of thromboembolic complication is rare but the result is fatal. In patients who continuing the OAT, post-operative bleeding can be controlled well with the local hemostatic measures. In the endodontic surgery, there are almost no studies about this issue. The intra-operative bleeding control is particularly important in the endodontic surgery because of its delicate and sensitive procedures such as inspection of resected root surface using dental microscope and retrograde filling. Further studies are necessary about this issue in the viewpoint of endodontic surgery.

Solubilization of glycoproteins of envelope viruses by detergents

International Nuclear Information System (INIS)

Berezin, V.E.; Zaides, V.M.; Artamsnov, A.F.; Isaeva, E.S.; Zhdanov, V.M.

1986-01-01

The action of a number of known ionic and nonionic detergents, as well as the new nonionic detergent MESK, on envelope viruses was investigated. It was shown that the nonionic detergents MESK, Triton X-100, and octyl-β-D-glucopyranoside selectively solubilize the outer glycoproteins of the virus particles. The nonionic detergent MESK has the mildest action. Using MESK, purified glycoproteins of influenza, parainfluenza, Venezuelan equine encephalomyelitis, vesicular stomatitis, rabies, and herpes viruses were obtained. The procedure for obtaining glycoproteins includes incubation of the virus suspension with the detergent MESK, removal of subvirus structures by centrifuging, and purification of glycoproteins from detergents by dialysis. Isolated glycoproteins retain a native structure and biological activity and possess high immunogenicity. The detergent MESK is promising for laboratory tests and with respect to the production of subunit vaccines

Fall risk and anticoagulation for atrial fibrillation in the elderly: A delicate balance.

Science.gov (United States)

Hagerty, Tracy; Rich, Michael W

2017-01-01

Guidelines for managing atrial fibrillation recommend systemic anticoagulation for almost all patients age 65 and older, but in practice up to 50% of older patients do not receive maintenance anticoagulation therapy. The most common reason physicians cite for withholding anticoagulation in older patients with atrial fibrillation is a perception of a high risk of falling and associated bleeding, especially intracranial hemorrhage. Copyright © 2017 Cleveland Clinic.

Hematin-derived anticoagulant. Generation in vitro and in vivo

OpenAIRE

1986-01-01

Prolongation of clotting times produced by hematin was investigated both in vitro and in vivo. Hematin-derived anticoagulant (HDA) was found to be due to a degradative product or derivative of hematin, and was generated in vitro in standing (aging) aqueous solutions of the parent compound. Generation of HDA in vitro was inhibited by antioxidants. The anticoagulant effect of HDA was inhibited by freshly prepared hematin, fresh Sn-protoporphyrin, imidazole, or the iron chelator desferrioxamine....

Nucleic acid-binding glycoproteins which solubilize nucleic acids in dilute acid: re-examination of the Ustilago maydis glycoproteins

Energy Technology Data Exchange (ETDEWEB)

Unrau, P.; Champ, D.R.; Young, J.L.; Grant, C.E.

1980-01-01

Holloman reported the isolation from Ustilago maydis of a glycoprotein which prevented the precipitation of nucleic acids in cold 5% trichloroacetic acid. Two glycoprotein fractions from U. maydis with this nucleic acid-solubilizing activity were isolated in our laboratory using improved purification procedures. The activity was not due to nuclease contamination. The glycoproteins are distinguished by: their ability to bind to concanavalin A-Sepharose; their differential binding to double- and single-stranded deoxyribonucleic acid, and to ribonucleic acid; their molecular weights (46,000 and 69,000); and the relative amounts present in growing versus nongrowing cells. Both fractions required sulfhydryl-reducing conditions for optimal yields, specific activity, and stability. Nucleic acid binding was cooperative, the minimum number of glycoproteins required to make a native T7 DNA molecule soluble in dilute acid being estimated at 2 and 15, respectively.

Structure of a trimeric variant of the Epstein-Barr virus glycoprotein B

Energy Technology Data Exchange (ETDEWEB)

Backovic, Marija [Northwestern Univ., Evanston, IL (United States); Longnecker, Richard [Northwestern Univ., Chicago, IL (United States); Jardetzky, Theodore S [Northwestern Univ., Evanston, IL (United States)

2009-03-16

Epstein-Barr virus (EBV) is a herpesvirus that is associated with development of malignancies of lymphoid tissue. EBV infections are life-long and occur in >90% of the population. Herpesviruses enter host cells in a process that involves fusion of viral and cellular membranes. The fusion apparatus is comprised of envelope glycoprotein B (gB) and a heterodimeric complex made of glycoproteins H and L. Glycoprotein B is the most conserved envelope glycoprotein in human herpesviruses, and the structure of gB from Herpes simplex virus 1 (HSV-1) is available. Here, we report the crystal structure of the secreted EBV gB ectodomain, which forms 16-nm long spike-like trimers, structurally homologous to the postfusion trimers of the fusion protein G of vesicular stomatitis virus (VSV). Comparative structural analyses of EBV gB and VSV G, which has been solved in its pre and postfusion states, shed light on gB residues that may be involved in conformational changes and membrane fusion. Also, the EBV gB structure reveals that, despite the high sequence conservation of gB in herpesviruses, the relative orientations of individual domains, the surface charge distributions, and the structural details of EBV gB differ from the HSV-1 protein, indicating regions and residues that may have important roles in virus-specific entry.

Characterization of Vesicular Stomatitis Virus Recombinants That Express and Incorporate High Levels of Hepatitis C Virus Glycoproteins

OpenAIRE

Buonocore, Linda; Blight, Keril J.; Rice, Charles M.; Rose, John K.

2002-01-01

We generated recombinant vesicular stomatitis viruses (VSV) expressing genes encoding hybrid proteins consisting of the extracellular domains of hepatitis C virus (HCV) glycoproteins fused at different positions to the transmembrane and cytoplasmic domains of the VSV G glycoprotein (E1G and E2G). We show that these chimeric proteins are transported to the cell surface and incorporated into VSV virions efficiently. We also generated VSV recombinants in which the gene encoding the VSV G protein...

Single-Molecular Imaging of Anticoagulation Factor I from Snake Venom by Atomic Force Microscopy

Institute of Scientific and Technical Information of China (English)

XU,Xiao-Long(徐小龙); ZHOU,Yun-Shen(周云申); LIU,Qing-Liang(刘清亮); HOU,Jian-Guo(侯建国); YANG,Jing-Long(杨金龙); XIE,Yong-Shu(解永树)

2002-01-01

Anticoagulation factor I (ACF I) from the venom of Agkistrodon acutus is a binding protein to activated coagulation factor X (FXa) and possesses marked anticoagulant activity. Single ACF I molecule has been successfully imaged in air by tapping mode atomic force microscopy (AFM) with high-resolution using glutaraldehyde as a coupling agent. The physical adsorption and covalent binding of ACF I onto the mica show very different surface topographies. The former exhibits the characteristic strand-like structure with much less reproducibility, the latter displays a elliptic granular structure with better reproducibility, which suggests that the stability of ACF I molecules on the mica is enhanced by covalent bonding in the presence of glutaraldehyde. A small-scale AFM amplitude-mode image clearly shows that the covalently bonded ACF I molecule by glutaraldehyde has olive shape structure with an average size of 7.4 nm× 3.6 nm × 3.1 nm, which is very similar to the size determined from the crystal structure of ACF I.

Heterofucans from Dictyota menstrualis have anticoagulant activity

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I.R.L. Albuquerque

2004-02-01

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

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

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M. Silingardi

2013-05-01

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

Oral Anticoagulation in Patients With Liver Disease.

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Qamar, Arman; Vaduganathan, Muthiah; Greenberger, Norton J; Giugliano, Robert P

2018-05-15

Patients with liver disease are at increased risks of both thrombotic and bleeding complications. Many have atrial fibrillation (AF) or venous thromboembolism (VTE) necessitating oral anticoagulant agents (OACs). Recent evidence has contradicted the assumption that patients with liver disease are "auto-anticoagulated" and thus protected from thrombotic events. Warfarin and non-vitamin K-antagonist OACs have been shown to reduce thrombotic events safely in patients with either AF or VTE. However, patients with liver disease have largely been excluded from trials of OACs. Because all currently approved OACs undergo metabolism in the liver, hepatic dysfunction may cause increased bleeding. Thus, the optimal anticoagulation strategy for patients with AF or VTE who have liver disease remains unclear. This review discusses pharmacokinetic and clinical studies evaluating the efficacy and safety of OACs in patients with liver disease and provides a practical, clinically oriented approach to the management of OAC therapy in this population. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

POST-NOAC: Portuguese observational study of intracranial hemorrhage on non-vitamin K antagonist oral anticoagulants.

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Marques-Matos, Cláudia; Alves, José Nuno; Marto, João Pedro; Ribeiro, Joana Afonso; Monteiro, Ana; Araújo, José; Silva, Fernando; Grenho, Fátima; Viana-Baptista, Miguel; Sargento-Freitas, João; Pinho, João; Azevedo, Elsa

2017-08-01

Background There is a lower reported incidence of intracranial hemorrhage with non-vitamin K antagonist oral anticoagulants compared with vitamin K antagonist. However, the functional outcome and mortality of intracranial hemorrhage patients were not assessed. Aims To compare the outcome of vitamin K antagonists- and non-vitamin K antagonist oral anticoagulants-related intracranial hemorrhage. Methods We included consecutive patients with acute non-traumatic intracranial hemorrhage on oral anticoagulation therapy admitted between January 2013 and June 2015 at four university hospitals. Clinical and demographic data were obtained from individual medical records. Intracranial hemorrhage was classified as intracerebral, extra-axial, or multifocal using brain computed tomography. Three-month functional outcome was assessed using the modified Rankin Scale. Results Among 246 patients included, 24 (9.8%) were anticoagulated with a non-vitamin K antagonist oral anticoagulants and 222 (90.2%) with a vitamin K antagonists. Non-vitamin K antagonist oral anticoagulants patients were older (81.5 vs. 76 years, p = 0.048) and had intracerebral hemorrhage more often (83.3% vs. 63.1%, p = 0.048). We detected a non-significant trend for larger intracerebral hemorrhage volumes in vitamin K antagonists patients ( p = 0.368). Survival analysis adjusted for age, CHA 2 DS 2 VASc, HAS-BLED, and anticoagulation reversal revealed that non-vitamin K antagonist oral anticoagulants did not influence three-month mortality (hazard ratio (HR) = 0.83, 95% confidence interval (CI) = 0.39-1.80, p = 0.638). Multivariable ordinal regression for three-month functional outcome did not show a significant shift of modified Rankin Scale scores in non-vitamin K antagonist oral anticoagulants patients (odds ratio (OR) 1.26, 95%CI 0.55-2.87, p = 0.585). Conclusions We detected no significant differences in the three-month outcome between non-vitamin K antagonist oral anticoagulants

The anticoagulant ability of ferulic acid and its applications for improving the blood compatibility of silk fibroin

Energy Technology Data Exchange (ETDEWEB)

Wang Song; Gao Zhen; Chen Xiaomeng; Lian Xiaojie; Zhu Hesun [School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Zheng Jun; Sun Lizhong [Department of Cardiac Surgery, Cardiovascular Institute and Fu Wai Hospital, CAMS and PUMC, Beijing 100037 (China)], E-mail: wangsongbit@hotmail.com

2008-12-15

The hemocompatibility of silk fibroin (SF) was improved with ferulic acid (FA) by graft polymerization. Ferulic acid is an active ingredient of many Chinese herbal medicines, such as Chuanxiong (Rhizoma ligustici wallichii), Danggui (Angelica sinensis) and Awei (Asafoetida giantfennel), which have been used to treat cardiovascular diseases by Chinese physicians for thousands of years. The inhibitory functions of FA on blood coagulation and erythrocyte agglutination were first characterized by a Lee-White test tube method and a micropipette technique, respectively. Then, FA was immobilized on SF by graft polymerization and the surface composition of modified SF was characterized by attenuated total reflectance Fourier-transform infrared (ATR-FTIR), x-ray photoelectron spectroscopy (XPS) and optical microscopy. The anticoagulant activity of modified SF was assessed, respectively, by in vitro clotting time measurements on a photo-optical clot detection instrument and with the Lee-White test tube method. The test results indicated that in comparison to untreated SF, the anticoagulant activity of modified SF has been improved significantly. Moreover, the SF surface composition is altered by FA but its {beta}-sheet conformation is not disturbed.

The effect anticoagulation status on geriatric fall trauma patients.

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Coleman, Julia; Baldawi, Mustafa; Heidt, David

2016-12-01

This research study aims to identify the effect of anticoagulation status on hospital course, complications, and outcomes among geriatric fall trauma patients. The study design is a retrospective cohort study, looking at fall trauma among patients aged 60 to 80 years from 2009 to 2013 at a university hospital in the United States. The statistical analysis, conducted with SPSS software with a threshold for statistical significance of P patients included in this study was 1,121. Compared with patients not on anticoagulation, there was a higher LOS among patients on anticoagulation (6.3 ± 6.2 vs 4.9 ± 5.2, P = .001). A higher LOS (7.2 ± 6.8 vs 5.0 ± 5.3, P = .001) and days in the ICU (2.1 ± 5.4 vs 1.1 ± 3.8, P = .010) was observed in patients on warfarin. A higher mortality (7.1% vs 2.8%, P = .013), LOS (6.3 ± 6.2 vs 5.1 ± 5.396, P = .036), and complication rate (49.1 vs 36.7, P = .010) was observed among patients on clopidogrel. In this study, a higher mortality and complication rate were seen among clopidogrel, and a greater LOS and number of days in the ICU were seen in patients on warfarin. These differences are important, as they can serve as a screening tool for triaging the severity of a geriatric trauma patient's condition and complication risk. For patients on clopidogrel, it is essential that these patients are recognized early as high-risk patients who will need to be monitored more closely. For patients on clopidogrel or warfarin, bridging a patient's anticoagulation should be initiated as soon as possible to prevent unnecessary increased LOS. At last, these data also provide support against prescribing patients clopidogrel when other anticoagulation options are available. Published by Elsevier Inc.

Will NOACs become the new standard of care in anticoagulation therapy?

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Ergene Oktay

2015-06-01

Full Text Available Atrial fibrillation is the most common cardiac arrhythmia in the general population, with a prevalence of 1–3%, which increases with age, reaching 15% in elderly people. Prophylaxis of ischemic stroke with warfarin was the gold standard of medical management for many years. On the other hand heparin and warfarin was the main pharmacologic agents for the prophylaxis/treatment of venous thromboembolism. In the last 5 years warfarin is getting replaced by non-vitamin K antagonist oral anticoagulants at least partly. In this article it is attempted to foresee whether new oral anticoagulants will become the new standard of care in anticoagulation therapy.

Citrate Anticoagulation for CRRT in Children: Comparison with Heparin

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Sara Nicole Fernández

2014-01-01

Full Text Available Regional anticoagulation with citrate is an alternative to heparin in continuous renal replacement therapies, which may prolong circuit lifetime and decrease hemorrhagic complications. A retrospective comparative cohort study based on a prospective observational registry was conducted including critically ill children undergoing CRRT. Efficacy, measured as circuit survival, and secondary effects of heparin and citrate were compared. 12 patients on CRRT with citrate anticoagulation and 24 patients with heparin anticoagulation were analyzed. Median citrate dose was 2.6 mmol/L. Median calcium dose was 0.16 mEq/kg/h. Median heparin dose was 15 UI/kg/h. Median circuit survival was 48 hours with citrate and 31 hours with heparin (P=0.028. 66.6% of patients treated with citrate developed mild metabolic alkalosis, which was directly related to citrate dose. There were no cases of citrate intoxication: median total calcium/ionic calcium index (CaT/I of 2.16 and a maximum CaT/I of 2.33, without metabolic acidosis. In the citrate group, 45.5% of patients developed hypochloremia and 27.3% hypomagnesemia. In the heparin group, 27.8% developed hypophosphatemia. Three patients were moved from heparin to citrate to control postoperatory bleeding. In conclusion citrate is a safe and effective anticoagulation method for CRRT in children and it achieves longer circuit survival than heparin.

Adverse effects of anticoagulation treatment: clinically significant upper gastrointestinal hemorrhage

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Pavel Skok

2006-12-01

Full Text Available Background: Over the last years, the use of oral anticoagulant treatment has increased dramatically, principally for the prevention of venous thrombosis and thrombembolic events. This treatment is demanding, especially among the elderly with concommitant diseases and different medication. Aim of the study to evaluate the rate of serious complications, clinically significant hemorrhage from upper gastointestinal tract in patients treated with oral antiocoagulants in a prospective cohort study.Patients and methods: Included were patients admitted to our institution between January 1, 1994 and December 31, 2003 due to gastrointestinal hemorrhage. Emergency endoscopy and laboratory testing was performed in all patients.Results: 6416 patients were investigated: 2452 women (38.2 % and 3964 men (61.8 %, mean age 59.1 years, SD 17.2. Among our patients, 55 % were aged over 60 years. In 86.4 % of patients the source of bleeding was confirmed in the upper gastrointestinal tract. In the last week prior to bleeding, 20.4 % (1309/6416 of all patients were regularly taking nonsteroidal anti-inflammatory drugs, anticoagulant therapy or antiplatelet agents in single daily doses at least. 6.3 % of patients (82/1309 with abundant hemorrhage from upper gastrointestinal tract were using oral anticoagulant therapy and had INR > 5 at admission, 25.6 % of them had INR > 10. The mortality of patients using oral anticoagulants and INR > 5 was 17.1 %.Conclusions: Upper gastrointestinal hemorrhage is a serious complication of different medications, particularly in elderly patients. Safe use of anticoagulant therapy is based on careful selection of patients and correct intake of the prescribed drugs.

RPE cell surface proteins in normal and dystrophic rats

International Nuclear Information System (INIS)

Clark, V.M.; Hall, M.O.

1986-01-01

Membrane-bound proteins in plasma membrane enriched fractions from cultured rat RPE were analyzed by two-dimensional gel electrophoresis. Membrane proteins were characterized on three increasingly specific levels. Total protein was visualized by silver staining. A maximum of 102 separate proteins were counted in silver-stained gels. Glycoproteins were labeled with 3H-glucosamine or 3H-fucose and detected by autoradiography. Thirty-eight fucose-labeled and 61-71 glucosamine-labeled proteins were identified. All of the fucose-labeled proteins were labeled with glucosamine-derived radioactivity. Proteins exposed at the cell surface were labeled by lactoperoxidase-catalyzed radioiodination prior to preparation of membranes for two-dimensional analysis. Forty separate 125I-labeled surface proteins were resolved by two-dimensional electrophoresis/autoradiography. Comparison with the glycoprotein map showed that a number of these surface labeled proteins were glycoproteins. Two-dimensional maps of total protein, fucose-labeled, and glucosamine-labeled glycoproteins, and 125I-labeled surface proteins of membranes from dystrophic (RCS rdy-p+) and normal (Long Evans or RCS rdy+p+) RPE were compared. No differences in the total protein or surface-labeled proteins were observed. However, the results suggest that a 183K glycoprotein is more heavily glycosylated with glucosamine and fucose in normal RPE membranes as compared to membranes from dystrophic RPE

Biosynthesis of ascites sialoglycoprotein-1, the major O-linked glycoprotein of 13762 rat mammary adenocarcinoma ascites cells

International Nuclear Information System (INIS)

Spielman, J.

1987-01-01

The present studies were undertaken to determine the timing of the major events in biosynthesis, and to characterize the contributions of chain initiation and elongation in maturation of the glycoprotein. Initiation of the earliest O-linked chains was detected by analysis of conversion of 3 H-thr to 3 H 2-aminobutyrate following mild alkaline borohydride elimination of O-linked sugars from peanut lectin-precipitated ASGP-1. Initiation was detected within 5 min of translation; amino sugar analysis of GlcNH 2 -labeled, trypsinized cells also showed that GalNAc was added as late as 5 min prior to arrival of ASGP-1 at the cell surface. Thus initiation occurs throughout biosynthesis. Maturation of the glycoprotein from a lightly-glycosylated immature form to the heavily-glycosylated mature from involved both continued initiation of new chains and chain elongation, and occurred with a half-time of about 30 min. Analysis of labeled ASGP-1 released from the cell surface by trypsinization showed that although some newly-synthesized ASGP-1 reached the cell surface within 70-80 min of protein synthesis, the half-time for appearance of mature glycoprotein was in excess of 4 hr, indicating that most molecules reside in an intracellular compartment(s) for a considerable time

Can we withdraw anticoagulation in patients with antiphospholipid syndrome after seroconvertion?

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Sciascia, S; Coloma-Bazán, E; Radin, M; Bertolaccini, M L; López-Pedrera, C; Espinosa, Gerard; Meroni, P L; Cervera, R; Cuadrado, M J

2017-11-01

The current mainstay of treatment in patients with thrombotic antiphospholipid syndrome (APS) is long-term anticoagulation, mainly with Vitamin K antagonist agents. Some recently available studies have created new ground for discussion about the possible discontinuation of anticoagulation therapy in patients with a history of thrombotic APS in whom antiphospholipid antibodies (aPL) are not detected any longer (i.e. aPL seroconversion). We report the main points discussed at the last CORA Meeting regarding the issue whether or not anticoagulation can be stopped after aPL seroconversion. In particular, we systematically reviewed the available evidence investigating the clinical outcome of APS patients with aPL seroconversion in whom anticoagulation was stopped when compared to those in whom therapy was continued regardless the aPL profile. Furthermore, the molecular basis for the aPL pathogenicity, the available evidence of non-criteria aPL and their association with thrombosis are addressed. To date, available evidence is still limited to support the indication to stop oral anticoagulation therapy in patients with a previous diagnosis of thrombotic APS who subsequently developed a negative aPL profile. The identification of the whole risk profile for cardiovascular manifestations and possibly of a second level aPL testing in selected patients with aPL might support the eventual clinical decision but further investigation is warranted. Copyright © 2017 Elsevier B.V. All rights reserved.

A comparative assessment of efficacy of three anticoagulant rodenticides.

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Renapurkar, D M

1982-01-01

Results are presented of feeding tests carried out with three common anticoagulant rodenticides viz., coumatetralyl, fumarin and warfarin on three common species of commensal rodents i.e., Rattus rattus, Rattus norvegicus and Bandicota bengalensis. All three species of rodents were susceptible to anticoagulant rodenticides. However, the action of these compounds in B. bengalensis was comparatively slow. Coumatetralyl was found to be the most effective rodenticide followed by fumarin and warfarin. Liquid baits of these compounds are more effective in comparison to food baits.

Chicken galectin-1B inhibits Newcastle disease virus adsorption and replication through binding to hemagglutinin-neuraminidase (HN) glycoprotein.

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Sun, Junfeng; Han, Zongxi; Qi, Tianming; Zhao, Ran; Liu, Shengwang

2017-12-08

Galectin-1 is an important immunoregulatory factor and can mediate the host-pathogen interaction via binding glycans on the surface of various viruses. We previously reported that avian respiratory viruses, including lentogenic Newcastle disease virus (NDV), can induce up-regulation of chicken galectin (CG)-1B in the primary target organ. In this study, we investigated whether CG-1B participated in the infectious process of NDV in chickens. We demonstrated that velogenic NDV induced up-regulation of CG-1B in target organs. We also found that CG-1B directly bound to NDV virions and inhibited their hemagglutination activity in vitro We confirmed that CG-1B interacted with NDV hemagglutinin-neuraminidase (HN) glycoprotein, in which the specific G4 N -glycans significantly contributed to the interaction between CG-1B and HN glycoprotein. The presence of extracellular CG-1B, rather than the internalization process, inhibited adsorption of NDV. The interaction between intracellular CG-1B and NDV HN glycoproteins inhibited cell-surface expression of HN glycoprotein and reduced the titer of progeny virus in NDV-infected DF-1 cells. Significantly, the replication of parental and HN glycosylation mutant viruses in CG-1B knockdown and overexpression cells demonstrated that the replication of NDV was correlated with the expression of CG-1B in a specific glycan-dependent manner. Collectively, our results indicate that CG-1B has anti-NDV activity by binding to N -glycans on HN glycoprotein. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Acute management of stroke patients taking non-vitamin K antagonist oral anticoagulants Addressing Real-world Anticoagulant Management Issues in Stroke (ARAMIS) Registry: Design and rationale.

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Xian, Ying; Hernandez, Adrian F; Harding, Tina; Fonarow, Gregg C; Bhatt, Deepak L; Suter, Robert E; Khan, Yosef; Schwamm, Lee H; Peterson, Eric D

2016-12-01

Non-vitamin K antagonist oral anticoagulants (NOACs, dabigatran, rivaroxaban, apixaban, and edoxaban) have been increasingly used as alternatives to warfarin for stroke prophylaxis in patients with atrial fibrillation. Yet there is substantial lack of information on how patients on NOACs are currently treated when they have an acute ischemic stroke and the best strategies for treating intracerebral hemorrhage for those on chronic anticoagulation with warfarin or a NOAC. These are critical unmet needs for real world clinical decision making in these emergent patients. The ARAMIS Registry is a multicenter cohort study of acute stroke patients who were taking chronic anticoagulation therapy prior to admission and are admitted with either an acute ischemic stroke or intracerebral hemorrhage. Built upon the existing infrastructure of American Heart Association/American Stroke Association Get With the Guidelines Stroke, the ARAMIS Registry will enroll a total of approximately 10,000 patients (5000 with acute ischemic stroke who are taking a NOAC and 5000 with anticoagulation-related intracerebral hemorrhage who are on warfarin or a NOAC). The primary goals of the ARAMIS Registry are to provide a comprehensive picture of current treatment patterns and outcomes of acute ischemic stroke patients on NOACs, as well as anticoagulation-related intracerebral hemorrhage in patients on either warfarin or NOACs. Beyond characterizing the index hospitalization, up to 2500 patients (1250 ischemic stroke and 1250 intracerebral hemorrhage) who survive to discharge will be enrolled in an optional follow-up sub-study and interviewed at 3 and 6 months after discharge to assess longitudinal medication use, downstream care, functional status, and patient-reported outcomes. The ARAMIS Registry will document the current state of management of NOAC treated patients with acute ischemic stroke as well as contemporary care and outcome of anticoagulation-related intracerebral hemorrhage. These

Characterization of mini-protein S, a recombinant variant of protein S that lacks the sex hormone binding globulin-like domain

NARCIS (Netherlands)

van Wijnen, M.; Stam, J. G.; Chang, G. T.; Meijers, J. C.; Reitsma, P. H.; Bertina, R. M.; Bouma, B. N.

1998-01-01

Protein S is a vitamin K-dependent glycoprotein involved in the regulation of the anticoagulant activity of activated protein C (APC). Also, an anticoagulant role for protein S, independent of APC, has been described. Protein S has a unique C-terminal sex hormone binding globulin (SHBG)-like domain

Abnormal uterine bleeding in women receiving direct oral anticoagulants for the treatment of venous thromboembolism.

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Godin, Richard; Marcoux, Violaine; Tagalakis, Vicky

2017-08-01

Abnormal uterine bleeding (AUB) is a common complication of anticoagulant therapy in premenopausal women affected with acute venous thromboembolism. AUB impacts quality of life, and can lead to premature cessation of anticoagulation. There is increasing data to suggest that the direct oral anticoagulants when used for the treatment of venous thromboembolism differ in their menstrual bleeding profile. This article aims to review the existing literature regarding the association between AUB and the direct oral anticoagulants and make practical recommendations. Copyright © 2017 Elsevier Inc. All rights reserved.

An improved radioimmunoassay for urinary Tamm-Horsfall glycoprotein

International Nuclear Information System (INIS)

Dawnay, A.B. St. J.; Thornley, C.; Cattell, W.R.

1982-01-01

A rapid specific radioimmunoassay has been used to measure Tamm-Horsfall glycoprotein (TH glycoprotein) in urine, and the method described. The apparent concentration increased with increasing dilution of urine in water, reaching a plateau at 1 in 20. This increase was greater the higher the osmolality and TH glycoprotein concentration and the lower the pH of the original sample. The apparent concentration of TH glycoprotein in neat or diluted urine was not affected by freezing or by storage at 4 0 C or room temperature for at least 2 days. A physiological range for the urinary excretion rate was established as 22-56 mg/24h, (considerably higher than the amount present in serum) based on samples from 29 individuals with normal renal function, as defined by their creatinine clearance. There was no significant correlation between serum concentrations of TH glycoprotein and its urinary excretion rate, nor between urinary excretion rate and creatinine clearance. (author)

Management of Periprocedural Anticoagulation: A Survey of Contemporary Practice.

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Flaker, Greg C; Theriot, Paul; Binder, Lea G; Dobesh, Paul P; Cuker, Adam; Doherty, John U

2016-07-12

Interruption of oral anticoagulation (AC) for surgery or an invasive procedure is a complicated process. Practice guidelines provide only general recommendations, and care of such patients occurs across multiple specialties. The availability of direct oral anticoagulants further complicates decision making and guidance here is limited. To evaluate current practice patterns in the United States for bridging AC, a survey was developed by the American College of Cardiology Anticoagulation Work Group. The goal of the survey was to assess how general and subspecialty cardiologists, internists, gastroenterologists, and orthopedic surgeons currently manage patients who receive AC and undergo surgery or an invasive procedure. The survey was completed by 945 physicians involved in the periprocedural management of AC. The results provide a template for educational and research projects geared toward the development of clinical pathways and point-of-care tools to improve this area of health care. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Use of antifibrinolytic mouthwash solution in anticoagulated oral surgery patients

OpenAIRE

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

2012-01-01

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

Orthobunyavirus ultrastructure and the curious tripodal glycoprotein spike.

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Thomas A Bowden

Full Text Available The genus Orthobunyavirus within the family Bunyaviridae constitutes an expanding group of emerging viruses, which threaten human and animal health. Despite the medical importance, little is known about orthobunyavirus structure, a prerequisite for understanding virus assembly and entry. Here, using electron cryo-tomography, we report the ultrastructure of Bunyamwera virus, the prototypic member of this genus. Whilst Bunyamwera virions are pleomorphic in shape, they display a locally ordered lattice of glycoprotein spikes. Each spike protrudes 18 nm from the viral membrane and becomes disordered upon introduction to an acidic environment. Using sub-tomogram averaging, we derived a three-dimensional model of the trimeric pre-fusion glycoprotein spike to 3-nm resolution. The glycoprotein spike consists mainly of the putative class-II fusion glycoprotein and exhibits a unique tripod-like arrangement. Protein-protein contacts between neighbouring spikes occur at membrane-proximal regions and intra-spike contacts at membrane-distal regions. This trimeric assembly deviates from previously observed fusion glycoprotein arrangements, suggesting a greater than anticipated repertoire of viral fusion glycoprotein oligomerization. Our study provides evidence of a pH-dependent conformational change that occurs during orthobunyaviral entry into host cells and a blueprint for the structure of this group of emerging pathogens.

Hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation.

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Marsh, E B; Llinas, R H; Hillis, A E; Gottesman, R F

2013-06-01

Intracerebral hemorrhage (ICH) can occur in patients following acute ischaemic stroke in the form of hemorrhagic transformation, and results in significant long-term morbidity and mortality. Anticoagulation theoretically increases risk. We evaluated stroke patients with an indication for anticoagulation to determine the factors associated with hemorrhagic transformation. Three-hundred and forty-five patients with ICD-9 codes indicating: (i) acute ischaemic stroke; and (ii) an indication for anticoagulation were screened. One-hundred and twenty-three met inclusion criteria. Data were collected retrospectively. Neuroimaging was reviewed for infarct volume and evidence of ICH. Hemorrhages were classified as: hemorrhagic conversion (petechiae) versus intracerebral hematoma (a space occupying lesion); symptomatic versus asymptomatic. Using multivariable logistic regression, we determined the hypothesized factors associated with intracerebral bleeding. Age [odds ratio (OR) = 1.50 per 10-year increment, 95% confidence interval (CI) 1.07-2.08], infarct volume (OR = 1.10 per 10 ccs, 95% CI 1.06-1.18) and worsening category of renal impairment by estimated glomerular filtration rate (eGFR; OR = 1.95, 95% CI 1.04-3.66) were predictors of hemorrhagic transformation. Ninety- nine out of 123 patients were anticoagulated. Hemorrhage rates of patients on and off anticoagulation did not differ (25.3% vs. 20.8%; P = 0.79); however, all intracerebral hematomas (n = 7) and symptomatic bleeds (n = 8) occurred in the anticoagulated group. The risk of hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation is multifactorial, and most closely associated with an individual's age, infarct volume and eGFR. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

Prediction of the risk of bleeding during anticoagulant treatment for venous thromboembolism

NARCIS (Netherlands)

Kuijer, P. M.; Hutten, B. A.; Prins, M. H.; Büller, H. R.

1999-01-01

OBJECTIVES: To construct and validate the bleeding risk prediction score, which is based on variables identified in the literature that can be easily obtained before the institution of anticoagulant therapy, in a large independent cohort of patients who were treated with anticoagulant therapy for

Anticoagulant rodenticide toxicity to non-target wildlife under controlled exposure conditions

Science.gov (United States)

Rattner, Barnett A.; Mastrota, F. Nicholas; van den Brink, Nico; Elliott, J.; Shore, R.; Rattner, B.

2018-01-01

Much of our understanding of anticoagulant rodenticide toxicity to non-target wildlife has been derived from molecular through whole animal research and registration studies in domesticated birds and mammals, and to a lesser degree from trials with captive wildlife. Using these data, an adverse outcome pathway identifying molecular initiating and anchoring events (inhibition of vitamin K epoxide reductase, failure to activate clotting factors), and established and plausible linkages (coagulopathy, hemorrhage, anemia, reduced fitness) associated with toxicity, is presented. Controlled exposure studies have demonstrated that second-generation anticoagulant rodenticides (e.g., brodifacoum) are more toxic than first- and intermediate-generation compounds (e.g., warfarin, diphacinone), however the difference in potency is diminished when first- and intermediate-generation compounds are administered on multiple days. Differences in species sensitivity are inconsistent among compounds. Numerous studies have compared mortality rate of predators fed prey or tissue containing anticoagulant rodenticides. In secondary exposure studies in birds, brodifacoum appears to pose the greatest risk, with bromadiolone, difenacoum, flocoumafen and difethialone being less hazardous than brodifacoum, and warfarin, coumatetralyl, coumafuryl, chlorophacinone and diphacinone being even less hazardous. In contrast, substantial mortality was noted in secondary exposure studies in mammals ingesting prey or tissue diets containing either second- or intermediate-generation compounds. Sublethal responses (e.g., prolonged clotting time, reduced hematocrit and anemia) have been used to study the sequelae of anticoagulant intoxication, and to some degree in the establishment of toxicity thresholds or toxicity reference values. Surprisingly few studies have undertaken histopathological evaluations to identify cellular lesions and hemorrhage associated with anticoagulant rodenticide exposure in non

Effect of post-filter anticoagulation on mortality in patients with cancer-associated pulmonary embolism.

Science.gov (United States)

Kang, Jieun; Kim, Seon Ok; Oh, Yeon-Mok; Lee, Sang-Do; Lee, Jae Seung

2018-05-17

Malignancy is associated with an increased risk of venous thromboembolism. Inferior vena cava filters are a viable alternative when anticoagulation is infeasible because of the risk of bleeding. Although the current guidelines recommend that all patients with a vena cava filter be treated with anticoagulation treatment when the risk of bleeding is reduced, studies concerning the role of concomitant anticoagulation after vena cava filter insertion in high-risk patients are scarce. Since many cancer patients suffer from a high risk of hemorrhagic complications, we aimed to determine the effect of post-filter anticoagulation on mortality in patients with a malignant solid tumor. A retrospective cohort study of patients with pulmonary embolism was performed between January 2010 and May 2016. Patients with a solid tumor and vena cava filter inserted because of pulmonary embolism were included. Using Cox proportional hazards model, the prognostic effect of clinical variables was analyzed. A total of 180 patients were analyzed, with 143 patients receiving and 37 patients not receiving post-filter anticoagulation treatment. Mortality was not significantly different between the two groups. The presence of metastatic cancer and that of pancreatobiliary cancer were significant risk factors for mortality. However, post-filter anticoagulation did not show significant effect on mortality regardless of the stage of cancer. In patients with cancer-associated pulmonary embolism, the effect of post-filter anticoagulation on mortality may not be critical, especially in patients with a short life expectancy.

Characterization of monomeric intermediates during VSV glycoprotein structural transition.

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Aurélie A Albertini

2012-02-01

Full Text Available Entry of enveloped viruses requires fusion of viral and cellular membranes, driven by conformational changes of viral glycoproteins. Crystal structures provide static pictures of pre- and post-fusion conformations of these proteins but the transition pathway remains elusive. Here, using several biophysical techniques, including analytical ultracentrifugation, circular dichroïsm, electron microscopy and small angle X-ray scattering, we have characterized the low-pH-induced fusogenic structural transition of a soluble form of vesicular stomatitis virus (VSV glycoprotein G ectodomain (G(th, aa residues 1-422, the fragment that was previously crystallized. While the post-fusion trimer is the major species detected at low pH, the pre-fusion trimer is not detected in solution. Rather, at high pH, G(th is a flexible monomer that explores a large conformational space. The monomeric population exhibits a marked pH-dependence and adopts more elongated conformations when pH decreases. Furthermore, large relative movements of domains are detected in absence of significant secondary structure modification. Solution studies are complemented by electron micrographs of negatively stained viral particles in which monomeric ectodomains of G are observed at the viral surface at both pH 7.5 and pH 6.7. We propose that the monomers are intermediates during the conformational change and thus that VSV G trimers dissociate at the viral surface during the structural transition.

Glycoprotein fucosylation is increased in seminal plasma of subfertile men

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Beata Olejnik

2015-04-01

Full Text Available Fucose, the monosaccharide frequent in N- and O-glycans, is a part of Lewis-type antigens that are known to mediate direct sperm binding to the zona pellucida. Such interaction was found to be inhibited in vitroby fucose-containing oligo- and polysaccharides, as well as neoglycoproteins. The objective of this study was to screen seminal plasma proteins of infertile/subfertile men for the content and density of fucosylated glycoepitopes, and compare them to samples of fertile normozoospermic subjects. Seminal proteins were separated in polyacrylamide gel electrophoresis and blotted onto nitrocellulose membrane and probed with fucose-specific Aleuria aurantia lectin (AAL. Twelve electrophoretic bands were selected for quantitative densitometric analysis. It was found that the content, and especially the density of fucosylated glycans, were higher in glycoproteins present in seminal plasma of subfertile men. No profound differences in fucosylation density were found among the groups of normozoospermic, oligozoospermic, asthenozoospermic, and oligoasthenozoospermic subfertile men. According to the antibody probing, AAL-reactive bands can be attributed to male reproductive tract glycoproteins, including prostate-specific antigen, prostatic acid phosphatase, glycodelin and chorionic gonadotropin. Fibronectin, α1 -acid glycoprotein, α1 -antitrypsin, immunoglobulin G and antithrombin III may also contribute to this high fucosylation. It is suggested that the abundant fucosylated glycans in the sperm environment could interfere with the sperm surface and disturb the normal course of the fertilization cascade.

Old and new oral anticoagulants for secondary stroke prevention in atrial fibrillation

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Tommaso Sacquegna

2015-12-01

Full Text Available Vitamin K antagonists, such as warfarin, used in oral anticoagulation therapy currently represent the standard drugs for the primary and secondary prevention of stroke in non-valvular atrial fibrillation (AF, with a relative risk reduction close to 70%. Newer oral anticoagulants, such as direct thrombin inhibitors (i.e., dabigatran and direct factor Xa inhibitors (i.e., apixaban and rivaroxaban have been recently compared with warfarin in large randomized trials for stroke prevention in AF. The new oral anticoagulants showed, compared with warfarin, no statistically significant difference in the rate of stroke or systemic embolism in secondary prevention (patients with previous transient ischemic attack or stroke subgroups. With regard to safety, the risk of intracranial bleeding was reduced with new anticoagulants compared with warfarin. Indirect treatment comparisons of clinical trials on secondary prevention cohorts showed no significant difference in efficacy among apixaban, rivaroxaban, and dabigatran; but dabigatran 110 mg was associated with less intracranial bleedings than rivaroxaban.

Clearance and binding of radiolabeled glycoproteins by cells of the murine mononuclear phagocyte system

International Nuclear Information System (INIS)

Imber, M.J.

1982-01-01

The clearance and binding of radiolabeled lactoferrin and fast α 2 -macroglobulin were studied. Both glycoproteins cleared rapidly following intravenous injection in mice, and both bound specifically to discrete receptors on murine peritoneal macrophages. The simultaneous presence of excess, unlabeled ligands specific for receptors recognizing terminal fucose, mannose, N-acetylglucosamine or galactose residues did not inhibit the clearance or binding of either lactoferrin or fast-α 2 M. The clearance and binding of enzymatically defucosylated lactoferrin was indistinguishable from native lactoferrin, indicating that terminal α(1-3)-linked fucose on lactoferrin is not necessary for receptor recognition. The clearance and binding of two fast -α 2 M forms, α 2 M-trypsin and α 2 M-MeNH 2 cross compete with each other. Saturation binding studies indicated that the total binding of mannosyl -BSA, fusocyl-BSA, and N-acetylglucosaminyl-BSA to macrophages activated by BCG was approximately 15% of the levels observed with inflammatory macrophages elicited by thioglycollate broth. Cross-competition binding studies demonstrated a common surface receptor mediated binding of all three neoglycoprotein ligands and was identical to the receptor on mononuclear phagocytes that binds mannosyl- and N-acetylglucosaminyl-terminated glycoproteins. These results suggest that difference between discrete states of macrophage function may be correlated with selective changes in levels of the surface receptor for mannose-containing glycoproteins

Characterization of canine herpesvirus glycoprotein C expressed by a recombinant baculovirus in insect cells.

Science.gov (United States)

Xuan, X; Maeda, K; Mikami, T; Otsuka, H

1996-12-01

The gene encoding the canine herpesvirus (CHV) glycoprotein C (gC) homologue has been identified by sequence homology analyses with other well studied herpesviruses. Previously, we have identified three CHV glycoproteins, gp145/112, gp80 and gp47 using a panel of monoclonal antibodies (MAbs). To determine which CHV glycoprotein corresponds to gC, a recombinant baculovirus which contains the putative CHV gC structural gene under the baculovirus polyhedrin promoter was constructed. The recombinant baculovirus expressed gC-related polypeptides (44-62 kDa), which reacted only with MAbs against CHV gp80, indicating that the previously identified CHV gp80 is the translation product of the gC gene. The baculovirus expressed gC was glycosylated and transported to the surface of infected cells. At least seven neutralizing epitopes were conserved on the gC produced in insect cells. It was found that the recombinant baculovirus infected cells adsorbed murine erythrocytes as is the case for CHV-infected cells. The hemadsorption activity was inhibited by heparin, indicating that the CHV gC binds to heparan sulfate on the surface of murine erythrocytes. Mice immunized with the recombinant gC produced strong neutralizing antibodies. Our results suggest that CHV gC produced in insect cells may be useful as a subunit vaccine to control CHV infections.

Direct anticoagulants and nursing: an approach from patient's safety.

Science.gov (United States)

Romero Ruiz, Adolfo; Romero-Arana, Adolfo; Gómez-Salgado, Juan

In recent years, a new line of treatment for the prevention of stroke in non-valvular atrial fibrillation, the so-called direct anticoagulants or new anticoagulants has appeared. The proper management and follow-up of these patients is essential to minimize their side effects and ensure patient safety. In this article, a description of these drugs is given, analyzing their characteristics, functioning and interactions together with the most habitual nursing interventions, as well as a reflection on the implications for the practice. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Receptor-Targeted Nipah Virus Glycoproteins Improve Cell-Type Selective Gene Delivery and Reveal a Preference for Membrane-Proximal Cell Attachment.

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Ruben R Bender

2016-06-01

Full Text Available Receptor-targeted lentiviral vectors (LVs can be an effective tool for selective transfer of genes into distinct cell types of choice. Moreover, they can be used to determine the molecular properties that cell surface proteins must fulfill to act as receptors for viral glycoproteins. Here we show that LVs pseudotyped with receptor-targeted Nipah virus (NiV glycoproteins effectively enter into cells when they use cell surface proteins as receptors that bring them closely enough to the cell membrane (less than 100 Å distance. Then, they were flexible in receptor usage as demonstrated by successful targeting of EpCAM, CD20, and CD8, and as selective as LVs pseudotyped with receptor-targeted measles virus (MV glycoproteins, the current standard for cell-type specific gene delivery. Remarkably, NiV-LVs could be produced at up to two orders of magnitude higher titers compared to their MV-based counterparts and were at least 10,000-fold less effectively neutralized than MV glycoprotein pseudotyped LVs by pooled human intravenous immunoglobulin. An important finding for NiV-LVs targeted to Her2/neu was an about 100-fold higher gene transfer activity when particles were targeted to membrane-proximal regions as compared to particles binding to a more membrane-distal epitope. Likewise, the low gene transfer activity mediated by NiV-LV particles bound to the membrane distal domains of CD117 or the glutamate receptor subunit 4 (GluA4 was substantially enhanced by reducing receptor size to below 100 Å. Overall, the data suggest that the NiV glycoproteins are optimally suited for cell-type specific gene delivery with LVs and, in addition, for the first time define which parts of a cell surface protein should be targeted to achieve optimal gene transfer rates with receptor-targeted LVs.

Isolation and characterization of anticoagulant compound from ...

African Journals Online (AJOL)

GIS

2013-10-02

Oct 2, 2013 ... The structural characterization of anticoagulant GAG was analyzed by Fourier transform infrared ... for pharmaceutical use are currently not available. However ... methods and sold live in the market for human consump- tion.

Determinants of foamy virus envelope glycoprotein mediated resistance to superinfection

International Nuclear Information System (INIS)

Berg, Angelika; Pietschmann, Thomas; Rethwilm, Axel; Lindemann, Dirk

2003-01-01

Little is known about the nature of foamy virus (FV) receptor molecules on target cells and their interaction with the viral glycoproteins. Similar to other viruses, cellular expression of the FV Env protein is sufficient to induce resistance to exogenous FV, a phenomenon called superinfection resistance (SIR). In this study we define determinants of the FV Env protein essential for mediating SIR. FV Env requires the extracellular domains of the SU and the TM subunits as well as membrane anchorage, efficient cell surface transport, and most probably correct subunit processing. This is in contrast to murine leukemia virus where secreted proteins comprising the receptor-binding domain in SU are sufficient to induce SIR. Furthermore, we demonstrate that cellular expression of the prototype FV envelope proteins induces SIR against pseudotypes with glycoproteins of other FV species, including of simian, feline, bovine, and equine origin. This implies that all of them use the same receptor molecules for viral entry

Anticoagulation in adults with congenital heart disease

DEFF Research Database (Denmark)

Jensen, A S; Idorn, L; Nørager, B

2015-01-01

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

[Seronegative antiphospholipid syndrome, catastrophic syndrome, new anticoagulants: learning from a difficult case report].

Science.gov (United States)

Joalland, F; de Boysson, H; Darnige, L; Johnson, A; Jeanjean, C; Cheze, S; Augustin, A; Auzary, C; Geffray, L

2014-11-01

The diagnosis of the antiphospholipid syndrome (APS) is based on clinical and biological criteria including the persistent presence of antiphospholipid antibodies and thrombotic events or pregnancy morbidity. Heparins relayed by vitamin K antagonists (VKA) are the gold standard treatment for thrombosis. We report a 17-year-old man who presented with an initially seronegative antiphospholipid syndrome, in whom the diagnosis was late, only obtained after anticoagulation withdrawing, when a catastrophic antiphospholipid syndrome (CAPS) with cutaneous lesions and disseminated intravascular coagulation syndrome occurred. For personal convenience, this patient was initially treated with fondaparinux followed by a new oral anticoagulant (rivaroxaban) before to return to the conventional VKA treatment. The "seronegative" APS is a controversial concept reflecting the heterogeneity of antigenic targets for aPL. This diagnosis may be considered after a rigorous work-up, with the help of haemostasis laboratories testing new emerging aPL assays. In APS, the new anticoagulants represent an attractive option needing nevertheless prospective studies to evaluate their safety and efficacy. Lupus anticoagulant detection in patients treated by new oral anticoagulants is not easy by usually recommended coagulation tests. Copyright © 2014. Published by Elsevier SAS.

Control of anticoagulant therapy and quality of life of patients with atrial fibrillation (review

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Shvarts Y.G.

2012-06-01

Full Text Available The review presents the published data on the relevance of the problem of thromboembolic complications in atrial fibrillation, the peculiarities of anticoagulant therapy for this disease. The relationship of clinical characteristics of patients with anticoagulant dose adjustment algorithms has been described. The problem of ethical issues of out of clinical trials patients and the dynamics of their quality of life against the background of long-term use of anticoagulant have been considered.

Does novel oral anticoagulant improve anticoagulation for non-valvular atrial fibrillation associated stroke: An inpatient registration study in Shanghai

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Feng-Di Liu

2015-12-01

Full Text Available Abstracts: Objective: To summarize the use rate, safety, efficacy of antithrombotics in stroke/transient ischemic attack (TIA prevention, and reasons for not using dabigatran etexilate (DE in Shanghai, China. Methods: Non-valvular atrial fibrillation (NVAF-associated stroke patients were prospectively registered as an electronic database. Use rate of antithrombotics and reasons for not using DE were extracted during follow-up. Patients' baseline characteristics, recurrent ischemic stroke/TIA events and bleeding complications were analyzed. Patients: From April 2012 to August 2014, 110 inpatients with NVAF-associated stroke were studied in our hospital. NVAF was diagnosed by 12-lead electrocardiogram, 24 h Holter and echocardiography. Results: Before introduction of DE (April 2013, use rates of warfarin and antiplatelets were 28.9% (11/38 and 60.5% (23/38 respectively; after that, use rates of warfarin, DE, and antiplatelets were 20.8% (15/72, 12.5% (9/72, and 43.1% (31/72. The DE did not improve use of anticoagulants (P = 0.639. There were 19 (17.3% recurrent ischemic stroke events up to October 2015; two (9.5% in the non-user group, 10 (18.5% in the antiplatelet group, and seven (20.0% in the anticoagulants group (P = 0.570. Furthermore, recurrence rates were similar between the DE group (20.0% and the Warfarin group (20.0%, P = 1.000. The most common reason for not using DE was financial concerns (61.0%, followed by inconvenience to purchase (14.0% and hemorrhage concerns (11.0%. Two patients using warfarin found fecal occult blood so they stopped warfarin and began to use antiplatelet drugs. No bleeding event occurred in the other groups. Only one patient had side effects (dyspepsia and gastroesophageal reflux from DE. Conclusion: The use rate of either DE or warfarin in Shanghai was low; DE had not improved anticoagulation therapy for NVAF patients in Shanghai mainly because DE had not been covered by health insurance. Keywords

Spontaneous pharyngo-laryngeal hematoma and anticoagulation. A case report

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Marleny CASASOLA-GIRÓN

2016-03-01

Full Text Available Introduction and Objective: Spontaneous pharyngeal-laryngeal hematoma shows the importance of a complete ENT examination in the face of symptoms of banal appearance and a correct history that, in the case reported, unveiled the therapeutic use of anticoagulants. Case description: A 55 year old woman comes to emergency because of unexplained dysphagia. The inspection shows the presence of a hematoma in the pharyngeal-laryngeal region that, after the anticoagulant therapy was reversed, evolved favorably with conservative treatment. Discussion: In this case, apart from medical management performed by the hematology department, we focus our therapeutic approach in the protection of the airway and the prevention of a possible massive bleeding. Determining which patients require endotracheal intubation or tracheostomy and hemostatic surgery is the key to treatment. Conclusions: The anticoagulant therapy involves several complications that ENT specialists must consider in the face of clinical symptoms of dysphagia, dysphonia, dyspnea or signs of bleeding and they must know the possibilities of performance depending on the severity of each case.

Anticoagulant and antimicrobial finishing of non-woven polypropylene textiles

International Nuclear Information System (INIS)

Degoutin, S; Jimenez, M; Casetta, M; Bellayer, S; Chai, F; Blanchemain, N; Neut, C; Kacem, I; Traisnel, M; Martel, B

2012-01-01

The aim of this work is to prepare non-woven polypropylene (PP) textile functionalized with bioactive molecules in order to improve its anticoagulation and antibacterial properties. This paper describes the optimization of the grafting process of acrylic acid (AA) on low-pressure cold-plasma pre-activated PP, the characterization of the modified substrates and the effect of these modifications on the in vitro biological response towards cells. Then, the immobilization of gentamicin (aminoglycoside antibiotic) and heparin (anticoagulation agent) has been carried out on the grafted samples by either ionic interactions or covalent linkages. Their bioactivity has been investigated and related to the nature of their interactions with the substrate. For gentamicin-immobilized AA-grafted samples, an inhibition radius and a reduction of 99% of the adhesion of Escherichia coli have been observed when gentamicin was linked by ionic interactions, allowing the release of the antibiotic. By contrast, for heparin-immobilized AA-grafted PP samples, a strong increase of the anticoagulant effect up to 35 min has been highlighted when heparin was covalently bonded on the substrate, by contact with the blood drop. (paper)

Single—Molecular Imaging of Anticoagulation Factor I From Snake Venom by Atomic Force Microscopy

Institute of Scientific and Technical Information of China (English)

徐小龙; 刘清亮; 等

2002-01-01

Anticoagulation factor I( ACF I) from the venom of Agki-strodom acutus is a binding protein to activanted coagulation fac tor X(FXa) and possesses marked anticoagulant acivity,Single ACF I molecule has been successfully imaged in air by tapping mode atomic force microscopy(AFM) with high-resolu-tion using glutaraldehyde as a coupling agent.The physical adsoprtion and covalent binding of ACF I onto the mica show very different surface topographies,The former exhibits the characteristic strand-like structure with much less reproducibility,the latter displays a elliptic granular structure with better repro-ducibility,which sugests that the stability of ACF I molecules on the mica is enhanced by covalent bonding in the presence of glutaraldehyde.A small-scale AFM amplitude -mode impage clearly shows that the covalently bonded ACF I molecule by glutaraldehyde has olive shape structure with an average size of 7.4nm×3.6nm×3.1nm ,which is very similar to the size determined from the crystal structure of ACF I.

Human platelet glycoprotein IX: An adhesive prototype of leucine-rich glycoproteins with flank-center-flank structures

International Nuclear Information System (INIS)

Hickey, M.J.; Williams, S.A.; Roth, G.J.

1989-01-01

The glycoprotein (GP) Ib-IX complex on the surface of human platelets functions as the von Willebrand factor receptor and mediates von Willebrand factor-dependent platelet adhesion to blood vessels. GPIX is a relatively small (M r , 17,000) protein that may provide for membrane insertion and orientation of the larger component of the complex. GPIb (M r , 165,000). Using antibody screening, the authors cloned a cDNA encoding GPIX from a human erythroleukemia cell cDNA library constructed in phage λgt11. Lacking a 5' untranslated region and start codon, the cDNA sequence includes 604 nucleotides, beginning with 495 bases at the 5' end coding for 165 amino acids, followed by a stop codon and 106 noncoding bases at the 3' end. By Northern blot analysis, the GPIX cDNA hybridizes with a single 1.0-kilobase species of platelet poly(A) + RNA. Translation of the cDNA sequence gives a predicted protein sequence beginning with a truncated putative signal sequence of 5 amino acids followed by a sequence of 17 amino acids matching that determined directly by Edman degradation of intact GPIX. GPIX contains a leucine-rich glycoprotein (LRG) sequence of 24 amino acids similar to conserved LRG sequences in GPIb and other proteins from humans, Drosophila, and yeast. The role of the flank-LRG center-flank structure in the evolution and function of the LRG proteins remains to be defined

Anticoagulant use for prevention of stroke in a commercial population with atrial fibrillation.

Science.gov (United States)

Patel, Aarti A; Lennert, Barb; Macomson, Brian; Nelson, Winnie W; Owens, Gary M; Mody, Samir H; Schein, Jeff

2012-07-01

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, and patients with AF are at an increased risk for stroke. Thromboprophylaxis with vitamin K antagonists reduces the annual incidence of stroke by approximately 60%, but appropriate thromboprophylaxis is prescribed for only approximately 50% of eligible patients. Health plans may help to improve quality of care for patients with AF by analyzing claims data for care improvement opportunities. To analyze pharmacy and medical claims data from a large integrated commercial database to determine the risk for stroke and the appropriateness of anticoagulant use based on guideline recommendations for patients with AF. This descriptive, retrospective claims data analysis used the Anticoagulant Quality Improvement Analyzer software, which was designed to analyze health plan data. The data for this study were obtained from a 10% randomly selected sample from the PharMetrics Integrated Database. This 10% sample resulted in almost 26,000 patients with AF who met the inclusion criteria for this study. Patients with a new or existing diagnosis of AF between July 2008 and June 2010 who were aged ≥18 years were included in this analysis. The follow-up period was 1 year. Demographics, stroke risk level (CHADS2 and CHA2DS2-VASc scores), anticoagulant use, and inpatient stroke hospitalizations were analyzed through the analyzer software. Of the 25,710 patients with AF (CHADS2 score 0-6) who were eligible to be included in this study, 9093 (35%) received vitamin K antagonists and 16,617 (65%) did not receive any anticoagulant. Of the patients at high risk for stroke, as predicted by CHADS2, 39% received an anticoagulant medication. The rates of patients receiving anticoagulant medication varied by age-group-16% of patients aged <65 years, 22% of those aged 65 to 74 years, and 61% of elderly ≥75 years. Among patients hospitalized for stroke, only 28% were treated with an anticoagulant agent in the outpatient

Graves’ Disease and Treatment Effects on Warfarin Anticoagulation

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Amanda Howard-Thompson

2014-01-01

Full Text Available Background. Hyperthyroidism causes an increased hypoprothrombinemic response to warfarin anticoagulation. Previous studies have demonstrated that patients with hyperthyroidism require lower dosages of warfarin to achieve a therapeutic effect. As hyperthyroidism is treated and euthyroidism is approached, patients may require increasing warfarin dosages to maintain appropriate anticoagulation. We describe a patient’s varying response to warfarin during treatment of Graves’ disease. Case Presentation. A 48-year-old African American female presented to the emergency room with tachycardia, new onset bilateral lower extremity edema, gradual weight loss, palpable goiter, and generalized sweating over the prior 4 months. She was admitted with Graves’ disease and new onset atrial fibrillation. Primary stroke prophylaxis was started using warfarin; the patient developed a markedly supratherapeutic INR likely due to hyperthyroidism. After starting methimazole, her free thyroxine approached euthyroid levels and the INR became subtherapeutic. She remained subtherapeutic over several months despite steadily increasing dosages of warfarin. Immediately following thyroid radioablation and discontinuation of methimazole, the patient’s warfarin dose and INR stabilized. Conclusion. Clinicians should expect an increased response to warfarin in patients with hyperthyroidism and close monitoring of the INR is imperative to prevent adverse effects. As patients approach euthyroidism, insufficient anticoagulation is likely without vigilant follow-up, INR monitoring, and increasing warfarin dosages.

Unexpected disappearance of portal cavernoma on long-term anticoagulation.

Science.gov (United States)

Silva-Junior, Gilberto; Turon, Fanny; Hernandez-Gea, Virginia; Darnell, Anna; García-Criado, Ángeles; García-Pagán, Juan Carlos

2014-08-01

Idiopathic non-cirrhotic portal hypertension is a rare disease of unknown etiology. Patients with idiopathic non-cirrhotic portal hypertension have an increased risk of developing portal vein thrombosis and this is especially prevalent when HIV is also present. We describe a unique case of a patient with idiopathic non-cirrhotic portal hypertension associated to HIV, who developed acute portal vein thrombosis that despite anticoagulation transformed in portal cavernoma and disappeared completely after five years of follow-up on continuous anticoagulation. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Hematology of Nile tilapia (Oreochromis niloticus subjected to anesthesia and anticoagulation protocols

Directory of Open Access Journals (Sweden)

Nadia Cristine Weinert

2015-12-01

Full Text Available Clinical hematology facilitates the diagnosis of disease and can act as a prognostic indicator of pathological conditions in fish. The aim of the present study was to evaluate hematological parameters of Nile tilapia (Oreochromis niloticus subjected to different anesthetics and anticoagulants. Thirty apparently healthy fishes (average weight of 473 ± 35. 50 g and mean total length of 29. 33 ± 0. 37 cm, were selected from the local commercial fish farm in the Lages municipality (Santa Catarina, Brazil. The animals were randomly divided into three groups of 10. In two groups, anesthesia was induced with eugenol (70 mg·L- 1 (EG and Benzocaine hydrochloride (100 mg·L-1 (BG, respectively. Anesthesia was not administered to fish of the third group (CG/control group. Blood samples were obtained by venipuncture of the caudal vessels and placed into microtubes containing sodium heparin or Na2EDTA for further analysis. The results were analyzed by Sigma Stat for Windows, the paired t-test for significant differences between anticoagulants of the same group, and analysis of variance followed by the Tukey test for comparison of means between groups (p ? 0. 05. Most of the observed changes in the erythrogram were significantly higher for the anticoagulant heparin and benzocaine group in comparison to the control group. However, the values obtained for the leukogram were significantly higher for all groups subjected to the Na2EDTA anticoagulant, suggesting that heparin may cause cell clumping. The results suggest that the anesthetics under investigation effectively minimizes the effects of stress caused by handling and invasive procedures, and that the anticoagulant heparin causes less hemolysis in comparison to Na2EDTA for Nile tilapia. Thus, the hematological variations attributed to different anesthetic protocols and/or different anticoagulants should be considered for the species Oreochromis niloticus.

Direct oral anticoagulants: what can we learn?

Science.gov (United States)

Marongiu, Francesco; Barcellona, Doris

2018-03-02

Direct oral anticoagulants (DOACs) represent an innovation because they avoid periodic laboratory monitoring, and also reduce cerebral bleeding. An examination of the performance of DOACs versus warfarin in randomized clinical trials dedicated to atrial fibrillation would reveal the poor performance of warfarin because the percentage of major bleeding is always above 3%; however, the percentage of major bleeding is less than half of that when the management is done in anticoagulation clinics (ACs). Several years ago, a common opinion was that ACs would disappear as soon as DOACs enter the market. We proposed then that ACs could be transformed into thrombosis centres (TCs) because we envisaged many new activities in terms of diagnostic tools and therapeutic choices. After the introduction of DOACs, the role of the ACs has been re-evaluated because their role may be crucial in selecting both the most appropriate diagnostic approach and the best therapeutic option (including anti-vitamin K drugs) for the single patient. TCs can organize a regular follow-up to improve patient adherence to DOACs. Marketing might have a role in the decision making of the single doctor. Efforts should be made for limiting the relationships between doctors and pharmaceutical companies. It seems reasonable to better prepare doctors, during their university courses, for them to develop a greater scientific culture that would enable them to critically read clinical studies and acquire an independent opinion. Ideally, an expert in haemostasis and thrombosis should handle new and old anticoagulants.

Improved anticoagulant effect of fucosylated chondroitin sulfate orally administered as gastro-resistant tablets.

Science.gov (United States)

Fonseca, Roberto J C; Sucupira, Isabela D; Oliveira, Stephan Nicollas M C G; Santos, Gustavo R C; Mourão, Paulo A S

2017-04-03

Fucosylated chondroitin sulfate (FucCS) is a potent anticoagulant polysaccharide extracted from sea cucumber. Its anticoagulant activity is attributed to the presence of unique branches of sulfated fucose. Although this glycosaminoglycan exerts an antithrombotic effect following oral administration, high doses are necessary to achieve the maximum effect. The diminished activity of FucCS following oral administration is likely due to its degradation in the gastrointestinal tract and its limited ability to cross the intestinal cell membranes. The latter aspect is particularly difficult to overcome. However, gastro-resistant tablet formulation may help limit the degradation of FucCS in the gastrointestinal tract. In the present work, we found that the oral administration of FucCS as gastro-resistant tablets produces a more potent and prolonged anticoagulant effect compared with its administration as an aqueous solution, with no significant changes in the bleeding tendency or arterial blood pressure. Experiments using animal models of arterial thrombosis initiated by endothelial injury demonstrated that FucCS delivered as gastro-protective tablets produced a potent antithrombotic effect, whereas its aqueous solution was ineffective. However, there was no significant difference between the effects of FucCS delivered as gastro-resistant tablets or as aqueous solution in a venous thrombosis model, likely due to the high dose of thromboplastin used. New oral anticoagulants tested in these experimental models for comparison showed significantly increased bleeding tendencies. Our study provides a framework for developing effective oral anticoagulants based on sulfated polysaccharides from marine organisms. The present results suggest that FucCS is a promising oral anticoagulant.

Flow cytometric analysis of platelet cyclooxygenase-1 and -2 and surface glycoproteins in patients with immune thrombocytopenia and healthy individuals.

Science.gov (United States)

Rubak, Peter; Kristensen, Steen D; Hvas, Anne-Mette

2017-06-01

Immature platelets may contain more platelet enzymes such as cyclooxygenase (COX)-1 and COX-2 than mature platelets. Patients with immune thrombocytopenia (ITP) have a higher fraction of immature platelets and can therefore be utilized as a biological model for investigating COX-1 and COX-2 platelet expression. The aims were to develop flow cytometric assays for platelet COX-1 and COX-2 and to investigate the COX-1 and COX-2 platelet expression, platelet turnover, and platelet glycoproteins in ITP patients (n = 10) compared with healthy individuals (n = 30). Platelet count and platelet turnover parameters (mean platelet volume (MPV), immature platelet fraction (IPF), and immature platelet count (IPC)) were measured by flow cytometry (Sysmex XE-5000). Platelet COX-1, COX-2, and the glycoproteins (GP)IIb, IX, Ib, Ia, and IIIa were all analyzed by flow cytometry (Navios) and expressed as median fluorescence intensity. COX analyses were performed in both whole blood and platelet rich plasma (PRP), whereas platelet glycoproteins were analyzed in whole blood only. ITP patients had significantly lower platelet count (55 × 10 9 /L) than healthy individuals (240 × 10 9 /L, p platelet count and IPC (both p-values Platelet COX-1 expression was higher in ITP patients than healthy individuals using whole blood (p COX-1 platelet turnover and COX-1 expression (all p-values platelet turnover and COX-1 and COX-2 expressions (all p-values platelet turnover in ITP patients (all p-values 0.14, rho = 0.11-0.28). In conclusion, ITP patients expressed higher COX-1 and platelet glycoprotein levels than healthy individuals. COX-1 and platelet glycoproteins demonstrated positive correlations with platelet turnover in ITP patients. In healthy individuals, COX-1 and COX-2 expression correlated positively with platelet turnover. PRP was more sensitive compared with whole blood as regards determination of COX. Therefore, PRP is the recommended matrix for investigating COX-1 and COX-2 in

Synthesis of novel liquid crystal compounds and their blood compatibility as anticoagulative materials

International Nuclear Information System (INIS)

Tu Mei; Cha Zhenhang; Feng Bohua; Zhou Changren

2006-01-01

The objective of this study was to synthesize new types of cholesteric liquid crystal compounds and study the anticoagulative properties of their composite membranes. Three kinds of cholesteric liquid crystal compounds were synthesized and characterized by infrared spectroscopy, differential scanning calorimetry and optical polarizing microscope. The polysiloxane, as a substrate, was blended with three liquid crystal compounds and was then used as membranes. The anticoagulative property of different polysiloxane liquid crystal composite membranes was identified by the blood compatibility tests. Three cholesteryl liquid crystals synthesized in this work contained hydrophilic soft chains and presented iridescent texture owned by cholesteric liquid crystals in the range of their liquid crystal state temperature, but only cholesteryl acryloyl oxytetraethylene glycol carbonate was in the liquid crystal state at body temperature. When liquid crystals were blended with polysiloxane to form polysiloxane/liquid crystal composite membranes, the haemocompatibility of these membranes could be improved to some extent. The blood compatibility of composite membranes whose hydrophilic property was the best was more excellent than that of other composite membranes, fewer platelets adhered and spread, and showed little distortion on the surface of materials

Optimizing the use of oral anticoagulant therapy for atrial fibrilation in primary care: a pharmacist-led intervention.

Science.gov (United States)

Virdee, Mandeep S; Stewart, Derek

2017-02-01

Background Updated evidence-based guidelines for the management of atrial fibrillation (AF) necessitate patient review, particularly with respect to oral anticoagulants, to ensure maximum health gain around stroke prophylaxis. Objective To quantify the level of anticoagulation utilisation in patients with a CHA 2 DS 2 -VASc ≥1/≥2 (male/female) according to evidence-based guidelines and to assess the impact of a pharmacist-led intervention to optimise therapy. Setting Fifteen general medical practices in Liverpool, North-West England with a practice population of 99,129. Method GRASP-AF software was employed to interrogate patient electronic medical records to identify and risk stratify AF patients (using CHA 2 DS 2 -VASc). A pharmacist then reviewed the medical records of those of patients not anticoagulated and with a CHA 2 DS 2 -VASc ≥1/≥2 (male/female). Recommendations were discussed with a general practitioner (GP) and those patients in whom the need for anticoagulation was agreed were invited for a consultation with either the pharmacist or GP and therapy optimised where appropriate. The GPs were responsible for managing those patients referred for diagnosis confirmation or further specialist opinion. Main outcome measure Proportion of patients eligible/not eligible for anticoagulation; proportions in whom anticoagulants initiated, refused, antiplatelets discontinued. Results Five hundred and twenty-three patients (31% of patients identified with AF and a CHA 2 DS 2 -VASc ≥1/≥2 (male/female)) were not receiving an anticoagulant (26 subsequently died or left the practice leaving 497). Three hundred and eighty-two (77%) pharmacist recommendations to a GP were agreed without modification. Following outcomes of diagnostic investigations and specialist referrals, 202 (41%) patients were candidates for anticoagulation, 251 (51%) were not eligible for anticoagulation, 103 (21%) were anticoagulated (56 warfarin, 47 DOAC). Conclusion A pharmacist

Recent developments in separation of low molecular weight heparin anticoagulants.

Science.gov (United States)

Sadowski, Radosław; Gadzała-Kopciuch, Renata; Buszewski, Bogusław

2017-10-05

The general function of anticoagulants is to prevent blood clotting and growing of the existing clots in blood vessels. In recent years, there has been a significant improvement in developing methods of prevention as well as pharmacologic and surgical treatment of thrombosis. For over the last two decades, low molecular weight heparins (LMWHs) have found their application in the antithrombotic diseases treatment. These types of drugs are widely used in clinical therapy. Despite the biological and medical importance of LMWHs, they have not been completely characterized in terms of their chemical structure. Due to both, the structural complexity of these anticoagulants and the presence of impurities, their structural characterization requires the employment of advanced analytical techniques. Since separation techniques play the key role in these endeavors, this review will focus on the presentation of recent developments in the separation of LMWH anticoagulants. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Secretion of hepatitis C virus envelope glycoproteins depends on assembly of apolipoprotein B positive lipoproteins.

Directory of Open Access Journals (Sweden)

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Full Text Available The density of circulating hepatitis C virus (HCV particles in the blood of chronically infected patients is very heterogeneous. The very low density of some particles has been attributed to an association of the virus with apolipoprotein B (apoB positive and triglyceride rich lipoproteins (TRL likely resulting in hybrid lipoproteins known as lipo-viro-particles (LVP containing the viral envelope glycoproteins E1 and E2, capsid and viral RNA. The specific infectivity of these particles has been shown to be higher than the infectivity of particles of higher density. The nature of the association of HCV particles with lipoproteins remains elusive and the role of apolipoproteins in the synthesis and assembly of the viral particles is unknown. The human intestinal Caco-2 cell line differentiates in vitro into polarized and apoB secreting cells during asymmetric culture on porous filters. By using this cell culture system, cells stably expressing E1 and E2 secreted the glycoproteins into the basal culture medium after one week of differentiation concomitantly with TRL secretion. Secreted glycoproteins were only detected in apoB containing density fractions. The E1-E2 and apoB containing particles were unique complexes bearing the envelope glycoproteins at their surface since apoB could be co-immunoprecipitated with E2-specific antibodies. Envelope protein secretion was reduced by inhibiting the lipidation of apoB with an inhibitor of the microsomal triglyceride transfer protein. HCV glycoproteins were similarly secreted in association with TRL from the human liver cell line HepG2 but not by Huh-7 and Huh-7.5 hepatoma cells that proved deficient for lipoprotein assembly. These data indicate that HCV envelope glycoproteins have the intrinsic capacity to utilize apoB synthesis and lipoprotein assembly machinery even in the absence of the other HCV proteins. A model for LVP assembly is proposed.

Subdural hematoma and oral anticoagulant therapy

NARCIS (Netherlands)

Wintzen, A. R.; Tijssen, J. G.

1982-01-01

In a retrospective study of the period 1959 to 1978, the role of anticoagulant therapy (ACT) in the development of subdural hematoma (SH) was investigated. Of 212 cases, 46 were receiving ACT, a proportion highly in excess of the frequency of ACT in the general population of the Leiden area. In this

Evaluation of Oral Anticoagulant-Associated Intracranial Parenchymal Hematomas Using CT Findings.

Science.gov (United States)

Gökçe, E; Beyhan, M; Acu, B

2015-06-01

Intracranial hemorrhage (ICH) is one of the most serious and lethal complications of anticoagulants with a reported incidence of 5-18.5 %. Computed tomographic (CT) findings, should be carefully studied because early diagnosis and treatment of oral anticoagulant use-associated hematomas are vitally important. In the present study, CT findings of intraparenchymal hematomas associated with anticoagulant and antihypertensive use are presented. This study included 45 patients (25 men, 20 women) under anticoagulant (21 patients) or antihypertensive (24 patients) treatment who had brain CT examinations due to complaints and findings suggesting cerebrovascular disease during July 2010-October 2013 period. CT examinations were performed to determine hematoma volumes and presence of swirl sign, hematocrit effect, mid-line shift effect, and intraventricular extension. The patients were 40-89 years of age. In four cases, a total of 51 intraparenchymal hematomas (42 cerebral, 7 cerebellar and 2 brain stem) were detected in multiple foci. Hematoma volumes varied from 0.09 to 284.00 ml. Swirl sign was observed in 87.5 and 63.0 % of OAC-associated ICHs and non-OAC-associated ICHs, respectively. In addition, hematocrit effect was observed in 41.6 % of OAC-associated and in 3.7 % of non-OAC-associated ICHs. Volume increases were observed in all 19 hematomas where swirl sign was detected, and follow-up CT scanning was conducted. Mortality of OAC-associated ICHs was correlated with initial volumes of hematoma, mid-line shift amount, and intraventricular extension. Detection of hematocrit effect by CT scanning of intracranial hematomas should be cautionary in oral anticoagulant use, while detection of swirl sign should be suggestive of active hemorrhage.

Replacement of the V3 domain in the surface subunit of the feline immunodeficiency virus envelope glycoprotein with the equivalent region of a T cell-tropic human immunodeficiency virus type 1 results in a chimeric surface protein that efficiently binds to CXCR4.

Science.gov (United States)

González, Silvia A; Falcón, Juan I; Affranchino, José L

2014-03-01

Feline immunodeficiency virus (FIV) and the T cell-tropic strains of human immunodeficiency virus type 1 (HIV-1) share the use of the chemokine receptor CXCR4 for cell entry. To study this process further we developed a cell surface binding assay based on the expression of a soluble version of the FIV SU C-terminally tagged with the influenza virus hemagglutinin epitope (HA). The specificity of the assay was demonstrated by the following evidence: (1) the SU-HA protein bound to HeLa cells that express CXCR4 but not to MDCK cells that lack this chemokine receptor; and (2) binding of the SU-HA to HeLa cells was blocked by incubation with the CXCR4 antagonist AMD3100 as well as with the anti-CXCR4 monoclonal antibody (MAb) 12G5. Deletion of the V3 region from the FIV SU glycoprotein abolished its ability to bind CXCR4-expressing cells. Remarkably, substitution of the V3 domain of the FIV SU by the equivalent region of the HIV-1 NL4-3 isolate resulted in efficient cell surface binding of the chimeric SU protein to CXCR4. Moreover, transfection of MDCK cells with a plasmid encoding human CXCR4 allowed the association of the chimeric SU-HA glycoprotein to the transfected cells. Interestingly, while cell binding of the chimeric FIV-HIV SU was inhibited by an anti-HIV-1 V3 MAb, its association with CXCR4 was found to be resistant to AMD3100. Of note, the chimeric FIV-HIV Env glycoprotein was capable of promoting CXCR4-dependent cell-to-cell fusion.

Isolation of allergenically active glycoprotein from Prosopis juliflora pollen.

Science.gov (United States)

Thakur, I S

1989-03-01

An allergenically active glycoprotein was homogeneously isolated from the aqueous extract of Prosopis juliflora pollen by ConA-Sepharose affinity chromatography. The molecular weight of this glycoprotein was 20,000 dalton, determined by gel filtration and SDS-PAGE. This fraction showed a total carbohydrate concentration of 25%. The purified glycoprotein revealed immunochemically most antigenic or allergenic and demonstrated homogeneous after reaction with P. juliflora pollen antiserum, characterized by gel diffusion, Immunoelectrophoresis and Radioallergosorbent test.

[Use of non-vitamin K antagonist oral anticoagulants in Primary Care: ACTUA study].

Science.gov (United States)

Barrios, V; Escobar, C; Lobos, J M; Polo, J; Vargas, D

2017-10-01

Approximately 40% of patients with non-valvular auricular fibrillation (NVAF) who receive vitamin K antagonists (VKA) in Primary Care in Spain have poor anticoagulation control. The objective of the study Actuación en antiCoagulación, Tratamiento y Uso de anticoagulantes orales de acción directa (ACOD) en Atención primaria (ACTUA) (Action in Coagulation, Treatment and Use of direct oral anticoagulants [DOACs]) in Primary Care) was to analyse the current situation regarding the use of VKA and non-vitamin K antagonist oral anticoagulants (NOACs) in patients with NVAF in Primary Care in Spain and the possible issues arising from it. An online survey was created covering various aspects of the use of oral anticoagulants in NAFV. A two-round modified Delphi approach was used. Results were compiled as a set of practical guidelines. Forty-four experts responded to the survey. Consensus was reached in 62% (37/60) of the items. Experts concluded that a considerable number of patients with NVAF who receive VKA do not have a well-controlled INR and that a substantial group of patients who could benefit from being treated with NOACs do not receive them. The use of NOACs increases the probability of having good anticoagulation control and decreases the risk of severe and intracranial haemorrhage. Current limitations to the use of NOACs include administrative barriers, insufficient knowledge about the benefits and risks of NOACs, limited experience of doctors in using them, and their price. Renal insufficiency influences the choice of a particular anticoagulant. The ACTUA study highlights the existing controversies about the use of oral anticoagulants for the treatment of NVAF in Primary Care in Spain, and provides consensus recommendations that may help to improve the use of these medications. Copyright © 2016 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

Improvement in long-term ECMO by detailed monitoring of anticoagulation: a case report.

Science.gov (United States)

Sievert, Alicia; Uber, Walter; Laws, Stacey; Cochran, Joel

2011-01-01

The use of unfractionated heparin (UFH) as an anticoagulant during long-term extracorporeal support presents a unique challenge for the clinician in balancing the amount of anticoagulant to maintain adequate anticoagulation without causing excessive bleeding. Activated clotting times (ACT) and activated partial thromboplastin times (aPTT) are the most common modality to monitor UFH on extracorporeal membrane oxygenation (ECMO). Limitations to these tests include consumptive coagulopathies, clotting factor deficiencies, platelet dysfunction, and fibrinolysis. The following case report describes the use of alternative monitoring strategies to assess more accurately anticoagulation during ECMO. A 20-month-old female presented to the emergency department with a 5-6 day history of cough, fever, tachypnea, and respiratory distress. She was diagnosed with influenza A and B with pneumonia. The patient was placed on veno-venous ECMO (V-V ECMO) after mechanical ventilation failed. On ECMO day eight, the patient developed a thrombus in her inferior vena cava and pleural effusions, obstructing cannula flow. Laboratory tests revealed the ACT was within range, yet the aPTT was dropping, despite increased heparin. Heparin levels were low and antithrombin-III (AT) concentrations were 40%. Recombinant AT was given and subsequent aPTTs were within the therapeutic range. Later, the aPTT decreased to 475 mg/ dL, and Factor VIII >150 IU/dL, suggesting an acute phase reaction or ongoing systemic inflammation, increasing the risk for thrombosis. We maintained heparin assays between 0.5-0.7 IU/mL and AT >60% to assure heparin's effect. The patient showed no signs of excess bleeding, blood product administration, or clots in the circuit, suggesting proper anticoagulation. The patient was successfully weaned on day 33 and is currently alive and at home. Monitoring of anti-Xa UFH and AT proved effective for measuring anticoagulation and detecting inconsistencies in other anticoagulation

Statement on the safety of glucosamine for patients receiving coumarin anticoagulants

DEFF Research Database (Denmark)

Tetens, Inge

2011-01-01

The European Food Safety Authority (EFSA) asked the Panel on Dietetic Products, Nutrition and Allergies to provide a scientific statement on the safety of glucosamine for patients receiving coumarin anticoagulants. More than 40 case reports have been collected by drug-monitoring agencies...... cases haemorrhage occurred in a variety of organs, and in one case this resulted in a persistent vegetative state. The evidence for an interaction between glucosamine and coumarin anticoagulants is strengthened by the observation that in the majority of cases the INR began to fall to normal values when...... glucosamine intake was discontinued. There is insufficient information to conclude on a mechanism for an interaction between glucosamine and coumarin anticoagulants. There are also insufficient data in the case reports to derive a dose-response relationship for glucosamine and to assess the level of risk...

Molecular cloning of complementary DNAs encoding the heavy chain of the human 4F2 cell-surface antigen: a type II membrane glycoprotein involved in normal and neoplastic cell growth

International Nuclear Information System (INIS)

Quackenbush, E.; Clabby, M.; Gottesdiener, K.M.; Barbosa, J.; Jones, N.H.; Strominger, J.L.; Speck, S.; Leiden, J.M.

1987-01-01

Complementary DNA (cDNA) clones encoding the heavy chain of the heterodimeric human membrane glycoprotein 4F2 have been isolated by immunoscreening of a λgt11 expression library. The identity of these clones has been confirmed by hybridization to RNA and DNA prepared from mouse L-cell transfectants, which were produced by whole cell gene transfer and selected for cell-surface expression of the human 4F2 heavy chain. DNA sequence analysis suggest that the 4F2 heavy-chain cDNAs encode an approximately 526-amino acid type II membrane glycoprotein, which is composed of a large C-terminal extracellular domain, a single potential transmembrane region, and a 50-81 amino acid N-terminal intracytoplasmic domain. Southern blotting experiments have shown that the 4F2 heavy-chain cDNAs are derived from a single-copy gene that has been highly conserved during mammalian evolution

Chimeric human parainfluenza virus bearing the Ebola virus glycoprotein as the sole surface protein is immunogenic and highly protective against Ebola virus challenge

International Nuclear Information System (INIS)

Bukreyev, Alexander; Marzi, Andrea; Feldmann, Friederike; Zhang Liqun; Yang Lijuan; Ward, Jerrold M.; Dorward, David W.; Pickles, Raymond J.; Murphy, Brian R.; Feldmann, Heinz; Collins, Peter L.

2009-01-01

We generated a new live-attenuated vaccine against Ebola virus (EBOV) based on a chimeric virus HPIV3/ΔF-HN/EboGP that contains the EBOV glycoprotein (GP) as the sole transmembrane envelope protein combined with the internal proteins of human parainfluenza virus type 3 (HPIV3). Electron microscopy analysis of the virus particles showed that they have an envelope and surface spikes resembling those of EBOV and a particle size and shape resembling those of HPIV3. When HPIV3/ΔF-HN/EboGP was inoculated via apical surface of an in vitro model of human ciliated airway epithelium, the virus was released from the apical surface; when applied to basolateral surface, the virus infected basolateral cells but did not spread through the tissue. Following intranasal (IN) inoculation of guinea pigs, scattered infected cells were detected in the lungs by immunohistochemistry, but infectious HPIV3/ΔF-HN/EboGP could not be recovered from the lungs, blood, or other tissues. Despite the attenuation, the virus was highly immunogenic, and a single IN dose completely protected the animals against a highly lethal intraperitoneal challenge of guinea pig-adapted EBOV

Oral anticoagulants for stroke prevention in atrial fibrillation.

Science.gov (United States)

Senoo, Keitaro; Lane, Deirdre A; Lip, Gregory Y H

2014-09-01

The availability of 4 non-vitamin K oral anticoagulants (NOACs), that is, dabigatran, rivaroxaban, apixaban, and edoxaban, has changed the landscape of stroke prevention in patients with atrial fibrillation. This review article provides an overview of the 4 phase III studies that have compared these NOACs, examining major outcomes of efficacy and safety. A range of practical questions relating to the NOACs have emerged, including topics such as patient selection, treating patients with renal impairment, treating elderly patients, and combining anticoagulant therapy with antiplatelet drugs. We also address the interaction of various patient characteristics with the treatments and suggest the features can assist the physician in the choice of a particular NOAC for a particular patient(s). Copyright © 2014 Elsevier B.V. All rights reserved.

Transportation cost of anticoagulation clinic visits in an urban setting.

Science.gov (United States)

Hwang, Jamie M; Clemente, Jennifer; Sharma, Krishna P; Taylor, Thomas N; Garwood, Candice L

2011-10-01

Patients being managed on warfarin make frequent or regular visits to anticoagulation monitoring appointments. International studies have evaluated transportation cost and associated time related to anticoagulation clinic visits. To our knowledge, no studies have evaluated the cost of transportation to such clinic visits in the United States. To describe the methods of transportation and estimate the average total cost of transportation to and from an anticoagulation clinic in an urban setting. We prospectively conducted a survey of patients treated at the Harper Anticoagulation Clinic located in Detroit, Michigan, during November 2010. The survey was given to patients while waiting at their regularly scheduled clinic appointments and included questions regarding mode of transportation, distance traveled in miles, parking payment, and time missed from work for clinic appointments. The mean distance traveled was translated into cost assuming 50 cents per mile based on 2010 estimates by the Internal Revenue Service. Sixty patients responded to the 11-item survey; response rates for individual items varied because participants were instructed to skip questions that did not pertain to them. Of the 47 participants responding to demographic questions, 70.2% were female, and 46.8% were older than 60 years. Transportation by private vehicle (80.0%), either driven by patients (41.7%) or someone else (38.3%), was the most common method reported. Use of private automobile translated into a cost of $11.19 per round trip. Other means of transportation identified include a ride from a medical transportation service (10.0%), bus (5.0%), walking (3.3%), and taxi (1.7%). The mean (SD) distance traveled to the clinic for all methods of transportation was 8.34 (7.7) miles. We estimated the average cost of round-trip transportation to be $10.78 weighted for all transportation modes. This is a direct nonmedical cost that is paid for by most patients out of pocket. However, 9 of 44 (20

Real life anticoagulation treatment of patients with atrial fibrillation in Germany

DEFF Research Database (Denmark)

Wilke, Thomas; Groth, Antje; Pfannkuche, Matthias

2015-01-01

Oral anticoagulation (OAC) with either new oral anticoagulants (NOACs) or Vitamin-K antagonists (VKAs) is recommended by guidelines for patients with atrial fibrillation (AF) and a moderate to high risk of stroke. Based on a claims-based data set the aim of this study was to quantify the stroke-r...... that both patient/disease characteristics and treatment environment/general prescribing behaviour of physicians may explain the OAC under-use in AF patients....

Non arteritic anterior ischemic optic neuropathy; does anticoagulation help?

International Nuclear Information System (INIS)

Aftab, A.M.; Iqbal, M.; Ali, A.; Rauf, A.

2017-01-01

Non Arteritic Anterior Ischemic Optic Neuropathy (NAION) is the most common acute optic neuropathy in patients over 50 years of age. This study was conducted to determine the beneficial effects of anticoagulation with Heparin and Warfarin in patients with NAION presenting within 4 weeks of onset of symptoms Methods: A prospective, interventional, pilot study was conducted in Eye- A unit of Khyber Teaching Hospital from July 2010 onwards on patients with NAION presenting within 4 weeks of onset of symptoms. Patients underwent complete ophthalmological examination including Snellen's visual acuity (latter converted to Log MAR), pupil examination, fundus examination and automated Humphrey visual field analysis. Hematologic tests, Thrombophilia screening, Echocardiography and carotid Doppler ultrasound were carried on patients. All patients were anticoagulated with Heparin and Warfarin after obtaining informed written consent. Patients were examined at 1 Month, 3 months and 6 months' time period. Primary parameter measured was improvement in visual acuity. Results: Total number of patients in our study was 24. Regarding visual outcome total number of patients having significant improvement of visual acuity in our study was 16 (66.6 percent), while 4 (16.7 percent) patients had marginal improvement of visual acuity. Three (12.5 percent) patients maintained stable visual acuity of 6/6 throughout the study period in presence of thrombophilic disorders. One patient (4.1 percent) suffered a decline in visual acuity compared to VA at baseline presentation. Conclusions: Anticoagulation using heparin and warfarin does benefit patients with NAION presenting within 4 weeks of onset of symptoms. In our study a higher proportion of patients experienced significant improvement of visual acuity following anticoagulation as compared to the highest reported spontaneous improvement in such patients. (author)

Anticoagulant factor V: factors affecting the integration of novel scientific discoveries into the broader framework.

Science.gov (United States)

LaBonte, Michelle L

2014-09-01

Since its initial discovery in the 1940s, factor V has long been viewed as an important procoagulant protein in the coagulation cascade. However, in the later part of the 20th century, two different scientists proposed novel anticoagulant roles for factor V. Philip Majerus proposed the first anticoagulant function for factor V in 1983, yet ultimately it was not widely accepted by the broader scientific community. In contrast, Björn Dahlbäck proposed a different anticoagulant role for factor V in 1994. While this role was initially contested, it was ultimately accepted and integrated into the scientific framework. In this paper, I present a detailed historical account of these two anticoagulant discoveries and propose three key reasons why Dahlbäck's anticoagulant role for factor V was accepted whereas Majerus' proposed role was largely overlooked. Perhaps most importantly, Dahlbäck's proposed anticoagulant role was of great clinical interest because the discovery involved the study of an important subset of patients with thrombophilia. Soon after Dahlbäck's 1994 work, this patient population was shown to possess the factor V Leiden mutation. Also key in the ultimate acceptance of the second proposed anticoagulant role was the persistence of the scientist who made the discovery and the interest in and ability of others to replicate and reinforce this work. This analysis of two different yet similar discoveries sheds light on factors that play an important role in how new discoveries are incorporated into the existing scientific framework. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

Functional Interplay Between Murine Leukemia Virus Glycogag, Serinc5, and Surface Glycoprotein Governs Virus Entry, with Opposite Effects on Gammaretroviral and Ebolavirus Glycoproteins

Directory of Open Access Journals (Sweden)

Yadvinder S. Ahi

2016-11-01

Full Text Available Gammaretroviruses, such as murine leukemia viruses (MLVs, encode, in addition to the canonical Gag, Pol, and Env proteins that will form progeny virus particles, a protein called “glycogag” (glycosylated Gag. MLV glycogag contains the entire Gag sequence plus an 88-residue N-terminal extension. It has recently been reported that glycogag, like the Nef protein of HIV-1, counteracts the antiviral effects of the cellular protein Serinc5. We have found, in agreement with prior work, that glycogag strongly enhances the infectivity of MLVs with some Env proteins but not those with others. In contrast, however, glycogag was detrimental to MLVs carrying Ebolavirus glycoprotein. Glycogag could be replaced, with respect to viral infectivity, by the unrelated S2 protein of equine infectious anemia virus. We devised an assay for viral entry in which virus particles deliver the Cre recombinase into cells, leading to the expression of a reporter. Data from this assay showed that both the positive and the negative effects of glycogag and S2 upon MLV infectivity are exerted at the level of virus entry. Moreover, transfection of the virus-producing cells with a Serinc5 expression plasmid reduced the infectivity and entry capability of MLV carrying xenotropic MLV Env, particularly in the absence of glycogag. Conversely, Serinc5 expression abrogated the negative effects of glycogag upon the infectivity and entry capability of MLV carrying Ebolavirus glycoprotein. As Serinc5 may influence cellular phospholipid metabolism, it seems possible that all of these effects on virus entry derive from changes in the lipid composition of viral membranes.

Intracellular localization of hydroxyproline-rich glycoprotein biosynthesis

International Nuclear Information System (INIS)

Robinson, D.G.; Andreae, M.; Glas, A.R.; Sauer, A.

1984-01-01

The structural proteins of plant cell walls are glycoproteins characterized by O-glucosidic linkages to hydroxyproline or serine. Proline, not hydroxyproline, is the translatable amino acid in hydroxyproline-rich glycoproteins (HRGP). Hydroxylation and arabinosylation of proline are sequential, post-translational events. Because of this, there is no a priori reason for expecting HRGP synthesis to follow the well-established route for secretory and plasma membrane (PM) glycoproteins, i.e., from endoplasmic reticulum (ER) via the Golgi apparatus (GA) to the PM. In this paper, two plausible alternatives for HRGO secretion are examined. Because a feature of the majority of dicotyledons is overlapping GA and PM regions in sucrose density gradients, the authors have used two monocotyledonous systems to determine the distribution of HRGP and enzyme activity

Analysis of glycoprotein-derived oligosaccharides in glycoproteins detected on two-dimensional gel by capillary electrophoresis using on-line concentration method.

Science.gov (United States)

Kamoda, Satoru; Nakanishi, Yasuharu; Kinoshita, Mitsuhiro; Ishikawa, Rika; Kakehi, Kazuaki

2006-02-17

Capillary electrophoresis (CE) is an effective tool to analyze carbohydrate mixture derived from glycoproteins with high resolution. However, CE has a disadvantage that a few nanoliters of a sample solution are injected to a narrow capillary. Therefore, we have to prepare a sample solution of high concentration for CE analysis. In the present study, we applied head column field-amplified sample stacking method to the analysis of N-linked oligosaccharides derived from glycoprotein separated by two-dimensional gel electrophoresis. Model studies demonstrated that we achieved 60-360 times concentration effect on the analysis of carbohydrate chains labeled with 3-aminobenzoic acid (3-AA). The method was applied to the analysis of N-linked oligosaccharides from glycoproteins separated and detected on PAGE gel. Heterogeneity of alpha1-acid glycoprotein (AGP), i.e. glycoforms, was examined by 2D-PAGE and N-linked oligosaccharides were released by in-gel digestion with PNGase F. The released oligosaccharides were derivatized with 3-AA and analyzed by CE. The results showed that glycoforms having lower pI values contained a larger amount of tetra- and tri-antennary oligosaccharides. In contrast, glycoforms having higher pI values contained bi-antennary oligosaccharides abundantly. The result clearly indicated that the spot of a glycoprotein glycoform detected by Coomassie brilliant blue staining on 2D-PAGE gel is sufficient for quantitative profiling of oligosaccharides.

Prevalence of Lupus Anticoagulant in Women with Spontaneous ...

African Journals Online (AJOL)

2017-10-26

Oct 26, 2017 ... ... pregnancy. Presence of lupus anticoagulant (LA), one of the antiphospholipid antibodies, ... pregnancy outcomes such as preeclampsia/eclampsia and small for date deliveries. ... changes in a background of APL syndrome.

Are pharmacological properties of anticoagulants reflected in pharmaceutical pricing and reimbursement policy? Out-patient treatment of venous thromboembolism and utilization of anticoagulants in Poland.

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Bochenek, T; Czarnogorski, M; Nizankowski, R; Pilc, A

2014-06-01

Pharmacotherapy with vitamin K antagonists (VKA) and low-molecular-weight heparins (LMWH) is a major cost driver in the treatment of venous thromboembolism (VTE). Major representatives of anticoagulants in Europe include: acenocoumarol and warfarin (VKA), enoxaparin, dalteparin, nadroparin, reviparin, parnaparin and bemiparin (LMWH). Aim of this report is to measure and critically assess the utilization of anticoagulants and other resources used in the out-patient treatment of VTE in Poland. To confront the findings with available scientific evidence on pharmacological and clinical properties of anticoagulants. The perspectives of the National Health Fund (NHF) and the patients were adopted, descriptive statistics methods were used. The data were gathered at the NHF and the clinic specialized in treatment of coagulation disorders. Non-pharmacological costs of treatment were for the NHF 1.6 times higher with VKA than with LMWH. Daily cost of pharmacotherapy with LMWH turned out higher than with VKA (234 times for the NHF, 42 times per patient). Within both LMWH and VKA the reimbursement due for the daily doses of a particular medication altered in the manner inversely proportional to the level of patient co-payment. Utilization of long-marketed and cheap VKA was dominated by LMWH, when assessed both through the monetary measures and by the actual volume of sales. Pharmaceutical reimbursement policy favored the more expensive equivalents among VKA and LMWH, whereas in the financial terms the patients were far better off when remaining on a more expensive alternative. The pharmaceutical pricing and reimbursement policy of the state should be more closely related to the pharmacological properties of anticoagulants.

Humanizing recombinant glycoproteins from Chinese hamster ovary cells

DEFF Research Database (Denmark)

Hansen, Anders Holmgaard; Amann, Thomas; Kol, Stefan

With new tools for gene-editing like zinc-fingers, TALENS and CRISPR, it is now feasible totailor-make the N-Glycoforms for therapeutic glycoproteins that have previously been almost impossible. We here demonstrate a case of humanizing a recombinant human glycoprotein that in Wild type (WT) Chinese...

Treatment Changes among Users of Non-Vitamin K Antagonist Oral Anticoagulants in Atrial Fibrillation

DEFF Research Database (Denmark)

Poulsen, Maja Hellfritzsch; Husted, Steen Elkjær; Grove, Erik Lerkevang

2017-01-01

Patients with atrial fibrillation discontinuing anticoagulant therapy are left unprotected against ischaemic stroke. Further, switching between oral anticoagulants may be associated with a transiently increased risk of bleeding or thromboembolism. However, there is a paucity of real-life data on ...

Practical recommendations for the choice of anticoagulants in the management of patients with atrial fibrillation on ibrutinib.

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Chai, Khai Li; Rowan, Gail; Seymour, John F; Burbury, Kate; Carney, Dennis; Tam, Constantine S

2017-12-01

The management of AF represents a major challenge in patients with CLL, especially in elderly patients with multiple comorbidities who are representative of the majority of patients with CLL. This is especially complex in the case of ibrutinib. Many anticoagulants have potential for pharmacological interaction with ibrutinib, and ibrutinib itself has antiplatelet properties. Use of ibrutinib therapy in these patients mandates review and revision of the need for anticoagulation and best anticoagulant to use. Herein, we review the current knowledge of the metabolism of common anticoagulants and how they may interact with ibrutinib.

A cost-analysis model for anticoagulant treatment in the hospital setting.

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Mody, Samir H; Huynh, Lynn; Zhuo, Daisy Y; Tran, Kevin N; Lefebvre, Patrick; Bookhart, Brahim

2014-07-01

Rivaroxaban is the first oral factor Xa inhibitor approved in the US to reduce the risk of stroke and blood clots among people with non-valvular atrial fibrillation, treat deep vein thrombosis (DVT), treat pulmonary embolism (PE), reduce the risk of recurrence of DVT and PE, and prevent DVT and PE after knee or hip replacement surgery. The objective of this study was to evaluate the costs from a hospital perspective of treating patients with rivaroxaban vs other anticoagulant agents across these five populations. An economic model was developed using treatment regimens from the ROCKET-AF, EINSTEIN-DVT and PE, and RECORD1-3 randomized clinical trials. The distribution of hospital admissions used in the model across the different populations was derived from the 2010 Healthcare Cost and Utilization Project database. The model compared total costs of anticoagulant treatment, monitoring, inpatient stay, and administration for patients receiving rivaroxaban vs other anticoagulant agents. The length of inpatient stay (LOS) was determined from the literature. Across all populations, rivaroxaban was associated with an overall mean cost savings of $1520 per patient. The largest cost savings associated with rivaroxaban was observed in patients with DVT or PE ($6205 and $2742 per patient, respectively). The main driver of the cost savings resulted from the reduction in LOS associated with rivaroxaban, contributing to ∼90% of the total savings. Furthermore, the overall mean anticoagulant treatment cost was lower for rivaroxaban vs the reference groups. The distribution of patients across indications used in the model may not be generalizable to all hospitals, where practice patterns may vary, and average LOS cost may not reflect the actual reimbursements that hospitals received. From a hospital perspective, the use of rivaroxaban may be associated with cost savings when compared to other anticoagulant treatments due to lower drug cost and shorter LOS associated with

The Need for Anticoagulation Following Inferior Vena Cava Filter Placement: Systematic Review

International Nuclear Information System (INIS)

Ray, Charles E.; Prochazka, Allan

2008-01-01

Purpose. To perform a systemic review to determine the effect of anticoagulation on the rates of venous thromboembolism (pulmonary embolus, deep venous thrombosis, inferior vena cava (IVC) filter thrombosis) following placement of an IVC filter. Methods. A comprehensive computerized literature search was performed to identify relevant articles. Data were abstracted by two reviewers. Studies were included if it could be determined whether or not subjects received anticoagulation following filter placement, and if follow-up data were presented. A meta-analysis of patients from all included studies was performed. A total of 14 articles were included in the final analysis, but the data from only nine articles could be used in the meta-analysis; five studies were excluded because they did not present raw data which could be analyzed in the meta-analysis. A total of 1,369 subjects were included in the final meta-analysis. Results. The summary odds ratio for the effect of anticoagulation on venous thromboembolism rates following filter deployment was 0.639 (95% CI 0.351 to 1.159, p = 0.141). There was significant heterogeneity in the results from different studies [Q statistic of 15.95 (p = 0.043)]. Following the meta-analysis, there was a trend toward decreased venous thromboembolism rates in patients with post-filter anticoagulation (12.3% vs. 15.8%), but the result failed to reach statistical significance. Conclusion. Inferior vena cava filters can be placed in patients who cannot receive concomitant anticoagulation without placing them at significantly higher risk of development of venous thromboembolism

[Retrospective analysis of correlative factors between digestive system injury and anticoagulant or antiplatelet-agents].

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Cui, Ning; Luo, Hesheng

2014-05-27

To explore the correlative factors and clinical characteristics of digestive system injury during the treatment of anticoagulant and (or) antiplatelet-agents. A total of 1 443 hospitalized patients on anticoagulant and (or) antiplatelet-agents from January 2010 to December 2013 at Renmin Hospital of Wuhan University were analyzed retrospectively. Their length of hospital stay was from 5 to 27 days. Most of them were elderly males (n = 880, 61.0%) with an average age of (62 ± 6) years. 1 138 patients (78.9%) were farmers, workers or someone without a specific occupation. During the treatment of anticoagulant/antiplatelet-agents, statistical difference existed (P = 0.01) between positively and negatively previous digestive disease groups for actively newly occurring digestive system injury (16.0% (41/256) vs 15.9% (189/1 187)). After the dosing of anticoagulant and (or) antiplatelet-agents, 57 (66.3%, 57/86) patients were complicated by hemorrhage of digestive tract, taking 62.9% (61/97) of all positive result patients for Helicobacter pylori test. Comparing preventive PPI group with no PPI group, there was no marked statistical differences (P = 2.67) for digestive system complication (including hemorrhage of digestive tract) while receiving anticoagulant and (or) antiplatelet-agents (13.9% (74/533) vs 17.1% (156/910)). During anticoagulant and/or antiplatelet-agent therapy, 185 patients (12.8%) were complicated by peptic ulcer or peptic ulcer with bleeding, 40 patients (2.8%) had erosive gastritis and 5 (0.3%) developed acute gastric mucosal lesions. And 42 of 76 patients complicated by hemorrhage of digestive tract underwent endoscopic hemostasis while 2 patients were operated. Ninety-seven patients (6.7%) died, including 61 (62.9%, 61/97) from hemorrhage of digestive tract. The remainder became cured, improved and discharged. Moreover, no significant statistical differences existed (P = 2.29) among three combination group (aspirin, clopidogrel, warfarin), two

Healthcare resources and needs in anticoagulant therapy for patients with nonvalvular atrial fibrillation. SAMOA Study.

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Barrios, V; Egocheaga-Cabello, M I; Gállego-Culleré, J; Ignacio-García, E; Manzano-Espinosa, L; Martín-Martínez, A; Mateo-Arranz, J; Polo-García, J; Vargas-Ortega, D

2017-05-01

To determine, in the various medical specialties, the healthcare process for anticoagulated patients with nonvalvular atrial fibrillation, to determine the available and necessary resources and to identify potential areas of improvement in the care of these patients. We performed a cross-sectional survey of primary care and specialised physicians involved in the care of anticoagulated patients. The questionnaires referred to the healthcare process, the indication and prescription of anticoagulant therapy and the barriers and deficiencies present for these patients. A total of 893 physicians participated in the study, 437 of whom worked in primary care and 456 of whom were specialists (mostly cardiologists). Forty-two percent of the family doctors indicated that they assessed and prescribed anticoagulant therapy, and 66% performed the regular follow-up of these patients. In both healthcare settings, the physicians noted the lack of standardised protocols. There was also a lack of quality control in the treatment. The role of primary care in managing anticoagulated patients has grown compared with previous reports. The responses of the participating physicians suggest marked gaps in the standardisation of the healthcare process and several areas for improvement in these patients' follow-up. The promotion of training in direct-acting anticoagulant drugs remains pivotal. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

Could Some Geriatric Characteristics Hinder the Prescription of Anticoagulants in Atrial Fibrillation in the Elderly?

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Paule Denoël

2014-01-01

Full Text Available Several studies have reported underprescription of anticoagulants in atrial fibrillation (AF. We conducted an observational study on 142 out of a total of 995 consecutive ≥75 years old patients presenting AF (14% when admitted in an emergency unit of a general hospital, in search of geriatric characteristics that might be associated with the underprescription of anticoagulation therapy (mostly antivitamin K at the time of the study. The following data was collected from patients presenting AF: medical history including treatment and comorbidities, CHADS2 score, ISAR scale (frailty, Lawton’s scale (ADL, GDS scale (mood status, MUST (nutrition, and blood analysis (INR, kidney function, and albumin. Among those patients for who anticoagulation treatment was recommended (73%, only 61% were treated with it. In the group with anticoagulation therapy, the following characteristics were observed more often than in the group without such therapy: a recent (≤6 months hospitalization and medical treatment including digoxin or based on >3 different drugs. Neither the value of the CHADS2 score, nor the geriatric characteristics could be correlated with the presence or the absence of an anticoagulation therapy. More research is thus required to identify and clarify the relative importance of patient-, physician-, and health care system-related hurdles for the prescription of oral anticoagulation therapy in older patients with AF.

Nonoclusive thrombosis of mechanical mitral valve prosthesis caused by inadequate treatment of anticoagulant therapy resistance

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Ivanović Branislava

2008-01-01

Full Text Available Background. Oral anticoagulants have been used in the prevention of thromboembolic complications for over six decades. A rare, but possible problem in the application of these medications could be resistance to them. Case report. We presented a patient with nonocclusive thrombosis of the mechanical mitral prosthesis due to inadequately treated resistance to peroral anticoagulant therapy. Resistance to oral anticoagulant medications was proven by an increased dosage of warfarin up to 20 mg and, after that, acenokumarol to 15 mg over ten days which did not lead to an increase in the international normalized ratio (INR value over 1.2. On the basis of information that she did not take food rich in vitamin K or medications which could reduce effects of oral anticoagulants, and that she did not have additional illnesses and conditions that could cause an inadequate response to anticoagulant therapy, it was circumstantially concluded that this was a hereditary form of resistance. Because of the existing mechanical prosthetics on the mitral position, low molecular heparin has been introduced into the therapy. The patient reduced it on her own initiative, leading to nonocclusive valvular thrombosis. Conclusion. When associated complications like absolute arrhithmia does not exist, the finding of resistance to oral anticoagulant agents is an indication for the replacement of a mechanical prosthetic with a biological one which has been done in this patients.

Anti-Coagulant and Anti-Thrombotic Properties of Blacklip Abalone (Haliotis rubra): In Vitro and Animal Studies.

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Suleria, Hafiz Ansar Rasul; Masci, Paul P; Zhao, Kong-Nan; Addepalli, Rama; Chen, Wei; Osborne, Simone A; Gobe, Glenda C

2017-08-04

Sulphated polysaccharides with anti-thrombotic and anti-coagulant activities have been found in various marine biota. In this study, a previously characterised anti-thrombotic and anti-coagulant extract from blacklip abalone was fractionated by anion exchange chromatography (AEC), pooled (on a sulphated polysaccharide basis) and administered to Wistar rats via oral gavage (N = 8) for assessment as an oral therapeutic. To ensure that the preparation had anti-coagulant activity prior to oral administration, it was assessed in rat blood by thromboelastography (TEG) significantly increasing reaction (R) time (or time until clot formation). Following in vitro confirmation of anti-coagulant activity, 40 mg of the preparation was orally administered to rats with blood samples collected at 2, 4, and 6 h post-gavage. Assessment of all blood samples by TEG showed some prolongation of R time from 355 to 380 s after 4 h. Dosing of the post-gavage blood samples with the abalone preparation to confirm anti-thrombotic activity in vitro revealed residual anti-coagulant activity, further suggesting that oral administration did increase anti-coagulant potential in the collected blood but that bioavailability was low. Assessment of tissues and haematological parameters showed no obvious harmful effects of the abalone preparation in animals. In summary, even though oral administration of fractionated and pooled blacklip abalone extract to rats delayed clotting after 4 h, bioavailability of the preparation appeared to be low and may be more appropriate for intravenous administration as an anti-thrombotic or anti-coagulant therapeutic.

Herpesvirus glycoproteins undergo multiple antigenic changes before membrane fusion.

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Daniel L Glauser

Full Text Available Herpesvirus entry is a complicated process involving multiple virion glycoproteins and culminating in membrane fusion. Glycoprotein conformation changes are likely to play key roles. Studies of recombinant glycoproteins have revealed some structural features of the virion fusion machinery. However, how the virion glycoproteins change during infection remains unclear. Here using conformation-specific monoclonal antibodies we show in situ that each component of the Murid Herpesvirus-4 (MuHV-4 entry machinery--gB, gH/gL and gp150--changes in antigenicity before tegument protein release begins. Further changes then occurred upon actual membrane fusion. Thus virions revealed their final fusogenic form only in late endosomes. The substantial antigenic differences between this form and that of extracellular virions suggested that antibodies have only a limited opportunity to block virion membrane fusion.

New insights into the Hendra virus attachment and entry process from structures of the virus G glycoprotein and its complex with Ephrin-B2.

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Kai Xu

Full Text Available Hendra virus and Nipah virus, comprising the genus Henipavirus, are recently emerged, highly pathogenic and often lethal zoonotic agents against which there are no approved therapeutics. Two surface glycoproteins, the attachment (G and fusion (F, mediate host cell entry. The crystal structures of the Hendra G glycoprotein alone and in complex with the ephrin-B2 receptor reveal that henipavirus uses Tryptophan 122 on ephrin-B2/B3 as a "latch" to facilitate the G-receptor association. Structural-based mutagenesis of residues in the Hendra G glycoprotein at the receptor binding interface document their importance for viral attachments and entry, and suggest that the stability of the Hendra-G-ephrin attachment complex does not strongly correlate with the efficiency of viral entry. In addition, our data indicates that conformational rearrangements of the G glycoprotein head domain upon receptor binding may be the trigger leading to the activation of the viral F fusion glycoprotein during virus infection.

An alternative conformation of the gp41 heptad repeat 1 region coiled coil exists in the human immunodeficiency virus (HIV-1) envelope glycoprotein precursor

International Nuclear Information System (INIS)

Mische, Claudia C.; Yuan Wen; Strack, Bettina; Craig, Stewart; Farzan, Michael; Sodroski, Joseph

2005-01-01

The human immunodeficiency virus (HIV-1) transmembrane envelope glycoprotein, gp41, which mediates virus-cell fusion, exists in at least three different conformations within the trimeric envelope glycoprotein complex. The structures of the prefusogenic and intermediate states are unknown; structures representing the postfusion state have been solved. In the postfusion conformation, three helical heptad repeat 2 (HR2) regions pack in an antiparallel fashion into the hydrophobic grooves on the surface of a triple-helical coiled coil formed by the heptad repeat 1 (HR1) regions. We studied the prefusogenic conformation of gp41 by mutagenic alteration of membrane-anchored and soluble forms of the HIV-1 envelope glycoproteins. Our results indicate that, in the HIV-1 envelope glycoprotein precursor, the gp41 HR1 region is in a conformation distinct from that of a trimeric coiled coil. Thus, the central gp41 coiled coil is formed during the transition of the HIV-1 envelope glycoproteins from the precursor state to the receptor-bound intermediate

Three-Dimensionally Functionalized Reverse Phase Glycoprotein Array for Cancer Biomarker Discovery and Validation.

Science.gov (United States)

Pan, Li; Aguilar, Hillary Andaluz; Wang, Linna; Iliuk, Anton; Tao, W Andy

2016-11-30

Glycoproteins have vast structural diversity that plays an important role in many biological processes and have great potential as disease biomarkers. Here, we report a novel functionalized reverse phase protein array (RPPA), termed polymer-based reverse phase glycoprotein array (polyGPA), to capture and profile glycoproteomes specifically, and validate glycoproteins. Nitrocellulose membrane functionalized with globular hydroxyaminodendrimers was used to covalently capture preoxidized glycans on glycoproteins from complex protein samples such as biofluids. The captured glycoproteins were subsequently detected using the same validated antibodies as in RPPA. We demonstrated the outstanding specificity, sensitivity, and quantitative capabilities of polyGPA by capturing and detecting purified as well as endogenous α-1-acid glycoprotein (AGP) in human plasma. We further applied quantitative N-glycoproteomics and the strategy to validate a panel of glycoproteins identified as potential biomarkers for bladder cancer by analyzing urine glycoproteins from bladder cancer patients or matched healthy individuals.

Glycoprotein Enrichment Analytical Techniques: Advantages and Disadvantages.

Science.gov (United States)

Zhu, R; Zacharias, L; Wooding, K M; Peng, W; Mechref, Y

2017-01-01

Protein glycosylation is one of the most important posttranslational modifications. Numerous biological functions are related to protein glycosylation. However, analytical challenges remain in the glycoprotein analysis. To overcome the challenges associated with glycoprotein analysis, many analytical techniques were developed in recent years. Enrichment methods were used to improve the sensitivity of detection, while HPLC and mass spectrometry methods were developed to facilitate the separation of glycopeptides/proteins and enhance detection, respectively. Fragmentation techniques applied in modern mass spectrometers allow the structural interpretation of glycopeptides/proteins, while automated software tools started replacing manual processing to improve the reliability and throughput of the analysis. In this chapter, the current methodologies of glycoprotein analysis were discussed. Multiple analytical techniques are compared, and advantages and disadvantages of each technique are highlighted. © 2017 Elsevier Inc. All rights reserved.

Reversing the Effect of Oral Anticoagulant Drugs: Established and Newer Options.

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Ansell, Jack E

2016-06-01

The vitamin K antagonists (VKAs) have been the standard (and only) oral anticoagulants used for the long-term treatment or prevention of venous thromboembolism or stroke in patients with atrial fibrillation. The coagulopathy induced by VKAs can be reversed with vitamin K, and in urgent situations, the vitamin K-dependent coagulation factors can be replaced by transfusion. In the last decade, a new class of oral anticoagulants has been developed, direct oral anticoagulants that bind to a specific coagulation factor and neutralize it. These compounds were shown to be effective and safe compared with the VKAs and were licensed for specific indications, but without a specific reversal agent. The absence of a reversal agent is a barrier to more widespread use of these agents. Currently, for the management of major life-threatening bleeding with the direct oral anticoagulants, most authorities recommend the use of four factor prothrombin complex concentrates. There are now three reversal agents in development and poised to enter the market. Idarucizumab is a specific antidote targeted to reverse the direct thrombin inhibitor, dabigatran, which was recently approved for use in the USA. Andexanet alfa is an antidote targeted to reverse the oral direct factor Xa inhibitors as well as the indirect inhibitor enoxaparin. Ciraparantag is an antidote targeted to reverse the direct thrombin and factor Xa inhibitors as well as the indirect inhibitor enoxaparin.

Efficacy and safety of a pharmacist-managed inpatient anticoagulation service for warfarin initiation and titration.

Science.gov (United States)

Wong, Y M; Quek, Y-N; Tay, J C; Chadachan, V; Lee, H K

2011-10-01

Anticoagulation consultations provided by a pharmacist-staffed inpatient service, similar to the experience reported in outpatient anticoagulation clinics, can potentially improve anticoagulation control and outcomes. At Tan Tock Seng Hospital, a 1200-bed acute care teaching hospital in Singapore, pharmacist-managed anticoagulation clinics have been in place since 1997. Pharmacist-managed services were extended to inpatient consultations in anticoagulation management from April 2006. Our objective was to assess the effect of implementing a pharmacist-managed inpatient anticoagulation service. This was a single-centre cohort study. Baseline data from 1 January 2006 to 31 March 2006 were collected and compared with post-implementation data from 1 April 2006 to 31 March 2007. Patients newly started on warfarin for deep vein thrombosis, pulmonary embolism or atrial fibrillation in general medicine and surgery departments were included. The three endpoints were as follows: (i) percentage of international normalized ratios (INRs) achieving therapeutic range within 5 days, (ii) INRs more than 4 during titration and (iii) subtherapeutic INRs on discharge. A total of 26 patients in the control period were compared with 144 patients who had received dosing consultations by a pharmacist during the initiation of warfarin. The provision of pharmacist consult resulted in 88% compared to 38% (P < 0·001) of INR values achieving therapeutic range within 5 days. There was a reduction in INR values of more than 4 during titration from 27% to 2% (P < 0·001), and subtherapeutic INR values on discharge without low molecular weight heparin from 15% to 0% (P < 0·001). The mean time to therapeutic INR was reduced from 6·5 to 3·9 days (P < 0·001) and mean length of stay after initiation of warfarin from 11 to 7·7 days (P = 0·004). Inpatient anticoagulation care and outcomes were significantly improved by a pharmacist-managed anticoagulation service. The time to therapeutic INR was

Trends in oral anticoagulant choice for acute stroke patients with nonvalvular atrial fibrillation in Japan: The SAMURAI‐NVAF Study

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Arihiro, Shoji; Todo, Kenichi; Yamagami, Hiroshi; Kimura, Kazumi; Furui, Eisuke; Terasaki, Tadashi; Shiokawa, Yoshiaki; Kamiyama, Kenji; Takizawa, Shunya; Okuda, Satoshi; Okada, Yasushi; Kameda, Tomoaki; Nagakane, Yoshinari; Hasegawa, Yasuhiro; Mochizuki, Hiroshi; Ito, Yasuhiro; Nakashima, Takahiro; Takamatsu, Kazuhiro; Nishiyama, Kazutoshi; Kario, Kazuomi; Sato, Shoichiro; Koga, Masatoshi; Nagatsuka, K; Minematsu, K; Nakagawara, J; Akiyama, H; Shibazaki, K; Maeda, K; Shibuya, S; Yoshimura, S; Endo, K; Miyagi, T; Osaki, M; Kobayashi, J; Okata, T; Tanaka, E; Sakamoto, Y; Takizawa, H; Takasugi, J; Tokunaga, K; Homma, K; Kinoshita, N; Matsuki, T; Higashida, K; Shiozawa, M; Kanai, H; Uehara, S

2015-01-01

Background Large clinical trials are lack of data on non‐vitamin K antagonist oral anticoagulants for acute stroke patients. Aim To evaluate the choice of oral anticoagulants at acute hospital discharge in stroke patients with nonvalvular atrial fibrillation and clarify the underlying characteristics potentially affecting that choice using the multicenter Stroke Acute Management with Urgent Risk‐factor Assessment and Improvement‐NVAF registry (ClinicalTrials.gov NCT01581502). Method The study included 1192 acute ischemic stroke/transient ischemic attack patients with nonvalvular atrial fibrillation (527 women, 77·7 ± 9·9 years old) between September 2011 and March 2014, during which three nonvitamin K antagonist oral anticoagulant oral anticoagulants were approved for clinical use. Oral anticoagulant choice at hospital discharge (median 23‐day stay) was assessed. Results Warfarin was chosen for 650 patients, dabigatran for 203, rivaroxaban for 238, and apixaban for 25. Over the three 10‐month observation periods, patients taking warfarin gradually decreased to 46·5% and those taking nonvitamin K antagonist oral anticoagulants increased to 48·0%. As compared with warfarin users, patients taking nonvitamin K antagonist oral anticoagulants included more men, were younger, more frequently had small infarcts, and had lower scores for poststroke CHADS 2, CHA 2 DS 2‐VASc, and HAS‐BLED, admission National Institutes of Health stroke scale, and discharge modified Rankin Scale. Nonvitamin K antagonist oral anticoagulants were started at a median of four‐days after stroke onset without early intracranial hemorrhage. Patients starting nonvitamin K antagonist oral anticoagulants earlier had smaller infarcts and lower scores for the admission National Institutes of Health stroke scale and the discharge modified Rankin Scale than those starting later. Choice of nonvitamin K antagonist oral anticoagulants was independently associated with 20‐day or

The bacteria binding glycoprotein salivary agglutinin (SAG/gp340) activates complement via the lectin pathway

NARCIS (Netherlands)

Leito, Jelani T. D.; Ligtenberg, Antoon J. M.; van Houdt, Michel; van den Berg, Timo K.; Wouters, Diana

2011-01-01

Salivary agglutinin (SAG), also known as gp-340 and Deleted in Malignant Brain Tumours 1, is a glycoprotein that is present in tears, lung fluid and mucosal surfaces along the gastrointestinal tract. It is encoded by the Deleted in Malignant Brain Tumours 1 gene, a member of the Scavenger Receptor

Encoding asymmetry of the N-glycosylation motif facilitates glycoprotein evolution.

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Ryan Williams

Full Text Available Protein N-glycosylation is found in all domains of life and has a conserved role in glycoprotein folding and stability. In animals, glycoproteins transit through the Golgi where the N-glycans are trimmed and rebuilt with sequences that bind lectins, an innovation that greatly increases structural diversity and redundancy of glycoprotein-lectin interaction at the cell surface. Here we ask whether the natural tension between increasing diversity (glycan-protein interactions and site multiplicity (backup and status quo might be revealed by a phylogenic examination of glycoproteins and NXS/T(X ≠ P N-glycosylation sites. Site loss is more likely by mutation at Asn encoded by two adenosine (A-rich codons, while site gain is more probable by generating Ser or Thr downstream of an existing Asn. Thus mutations produce sites at novel positions more frequently than the reversal of recently lost sites, and therefore more paths though sequence space are made available to natural selection. An intra-species comparison of secretory and cytosolic proteins revealed a departure from equilibrium in sequences one-mutation-away from NXS/T and in (A content, indicating strong selective pressures and exploration of N-glycosylation positions during vertebrate evolution. Furthermore, secretory proteins have evolved at rates proportional to N-glycosylation site number, indicating adaptive interactions between the N-glycans and underlying protein. Given the topology of the genetic code, mutation of (A is more often nonsynonomous, and Lys, another target of many PTMs, is also encoded by two (A-rich codons. An examination of acetyl-Lys sites in proteins indicated similar evolutionary dynamics, consistent with asymmetry of the target and recognition portions of modified sites. Our results suggest that encoding asymmetry is an ancient mechanism of evolvability that increases diversity and experimentation with PTM site positions. Strong selective pressures on PTMs may have

Local hemostatic measures in anticoagulated patients undergoing oral surgery: a systematized literature review

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Fábio Wildson Gurgel Costa

2013-01-01

Full Text Available PURPOSE: To conduct a systematized review of the literature about the main local hemostatic measures to control postoperative bleeding in anticoagulated patients. METHODS: A systematized review of literature was performed in the electronic database Medline (PubMed without restriction of the publication date. The eligibility criteria were studies involving maintenance of the anticoagulant therapy, prospective studies, retrospective studies, randomized clinical trials, controlled clinical studies, comparative studies, multicentric studies or case-control studies. Studies discontinuing anticoagulant therapy, case reports, literature reviews, in vitro studies, animal experiments and articles written in language not compatible with the search strategy adopted in this work were excluded. RESULTS: Twenty-four articles that met the adopted eligibility criteria were selected, enrolling 3891 subjects under anticoagulant therapy. A total of 171 cases of hemorrhage was observed. Tranexamic acid was the main local hemostatic measure used to controlling of postoperative bleeding. CONCLUSION: The local hemostatic measures proved to be effective according to previously published studies. Nevertheless, further clinical studies should be conducted to confirm this effectiveness.

Developing baculovirus-insect cell expression systems for humanized recombinant glycoprotein production

International Nuclear Information System (INIS)

Jarvis, Donald L.

2003-01-01

The baculovirus-insect cell expression system is widely used to produce recombinant glycoproteins for many different biomedical applications. However, due to the fundamental nature of insect glycoprotein processing pathways, this system is typically unable to produce recombinant mammalian glycoproteins with authentic oligosaccharide side chains. This minireview summarizes our current understanding of insect protein glycosylation pathways and our recent efforts to address this problem. These efforts have yielded new insect cell lines and baculoviral vectors that can produce recombinant glycoproteins with humanized oligosaccharide side chains

SMART: self-management of anticoagulation, a randomised trial [ISRCTN19313375].

Science.gov (United States)

McCahon, Deborah; Fitzmaurice, David A; Murray, Ellen T; Fuller, Christopher J; Hobbs, Richard F D; Allan, Teresa F; Raftery, James P

2003-09-18

Oral anticoagulation monitoring has traditionally taken place in secondary care because of the need for a laboratory blood test, the international normalised ratio (INR). The development of reliable near patient testing (NPT) systems for INR estimation has facilitated devolution of testing to primary care. Patient self-management is a logical progression from the primary care model. This study will be the first to randomise non-selected patients in primary care, to either self-management or standard care. The study was a multi-centred randomised controlled trial with patients from 49 general practices recruited. Those suitable for inclusion were aged 18 or over, with a long term indication for oral anticoagulation, who had taken warfarin for at least six months. Patients randomised to the intervention arm attended at least two training sessions which were practice-based, 1 week apart. Each patient was assessed on their capability to undertake self management. If considered capable, they were given a near patient INR testing monitor, test strips and quality control material for home testing. Patients managed their own anticoagulation for a period of 12 months and performed their INR test every 2 weeks. Control patients continued with their pre-study care either attending hospital or practice based anticoagulant clinics. The methodology used in this trial will overcome concerns from previous trials of selection bias and relevance to the UK health service. The study will give a clearer understanding of the benefits of self-management in terms of clinical and cost effectiveness and patient preference.

SMART: Self-Management of Anticoagulation, a Randomised Trial [ISRCTN19313375

Directory of Open Access Journals (Sweden)

Murray Ellen T

2003-09-01

Full Text Available Abstract Background Oral anticoagulation monitoring has traditionally taken place in secondary care because of the need for a laboratory blood test, the international normalised ratio (INR. The development of reliable near patient testing (NPT systems for INR estimation has facilitated devolution of testing to primary care. Patient self-management is a logical progression from the primary care model. This study will be the first to randomise non-selected patients in primary care, to either self-management or standard care. Method The study was a multi-centred randomised controlled trial with patients from 49 general practices recruited. Those suitable for inclusion were aged 18 or over, with a long term indication for oral anticoagulation, who had taken warfarin for at least six months. Patients randomised to the intervention arm attended at least two training sessions which were practice-based, 1 week apart. Each patient was assessed on their capability to undertake self management. If considered capable, they were given a near patient INR testing monitor, test strips and quality control material for home testing. Patients managed their own anticoagulation for a period of 12 months and performed their INR test every 2 weeks. Control patients continued with their pre-study care either attending hospital or practice based anticoagulant clinics. Discussion The methodology used in this trial will overcome concerns from previous trials of selection bias and relevance to the UK health service. The study will give a clearer understanding of the benefits of self-management in terms of clinical and cost effectiveness and patient preference.

Direct Oral Anticoagulants: An Overview for the Interventional Radiologist

Energy Technology Data Exchange (ETDEWEB)

Kumar, Pradesh, E-mail: pradeshkumar@doctors.org.uk; Ravi, Rajeev, E-mail: rajeev.ravi@aintree.nhs.uk; Sundar, Gaurav, E-mail: gaurav.sundar@aintree.nhs.uk [Aintree University Hospitals NHS Foundation Trust, Radiology Department (United Kingdom); Shiach, Caroline, E-mail: caroline.shiach@aintree.nhs.uk [Aintree University Hospitals NHS Foundation Trust, Haematology Department (United Kingdom)

2017-03-15

The direct oral anticoagulants (DOACs) have emerged as a good alternative for the treatment of thromboembolic diseases, and their use in clinical practice is increasing rapidly. The DOACs act by blocking the activity of one single step in the coagulation cascade. These drugs act downstream in the common pathway of the coagulation cascade by directly antagonising the action of thrombin or factor Xa. The development of DOACs represents a paradigm shift from the oral vitamin K antagonists such as warfarin. This article aims to describe the properties of the currently available DOACs including pharmacology and dosing. We also address the strategies for periprocedural management and reversal of anticoagulation of patients treated with these agents.

Direct Oral Anticoagulants: An Overview for the Interventional Radiologist

International Nuclear Information System (INIS)

Kumar, Pradesh; Ravi, Rajeev; Sundar, Gaurav; Shiach, Caroline

2017-01-01

The direct oral anticoagulants (DOACs) have emerged as a good alternative for the treatment of thromboembolic diseases, and their use in clinical practice is increasing rapidly. The DOACs act by blocking the activity of one single step in the coagulation cascade. These drugs act downstream in the common pathway of the coagulation cascade by directly antagonising the action of thrombin or factor Xa. The development of DOACs represents a paradigm shift from the oral vitamin K antagonists such as warfarin. This article aims to describe the properties of the currently available DOACs including pharmacology and dosing. We also address the strategies for periprocedural management and reversal of anticoagulation of patients treated with these agents.

Dynamics of synthetic activity of RNA and glycoproteins in epithel cells of endometrium in heifers after ovulation

International Nuclear Information System (INIS)

Pivko, J.; Grafenau, P.; Uhrin, V.; Kopecny, V.

1998-01-01

Synchronized heifers (n=9) of Black Pied HF breed were slaughtered on 3rd, 6th and 9th day of sexual cycle (first day of estrus = 0). Excisions from basal part (A) and functional part (B) of uteri were taken immediately after killing and were processed for autoradiographic analyses. The samples of endometrium were incubated for 20 minutes in isotonic medium with 100 micro Ci uridine (5 -3H) additive with specific activity 740 GBq/mM (UVVVR Prague) to study the RNA synthesis. The endometrium samples were incubated for 60 minutes, and 240 minutes in isotonic medium with 100 micro Ci L-(6-3 H) fucose with specific activity 0.55-1.1 TBqImM (Amersham Int., G.B.) for autoradiographic analysis of the glycoprotein synthesis. The samples were fixed, dehydrated and embedded in Epon 812 after the incubation. The prepared cuts were covered with photographic emulsion and stored in dark box in a refrigerator at 5øC. They were developed in the developer ORWO D 19, stained with methylene blue and examined through the light microscope after one month exposition. We found out by the autoradiographic analysis that the activity of RNA synthesis in cells of the surface epithel is of rising tendency from 3rd to 9th day. The intensity of RNA synthesis does not change in the functional zone during the early lutheal phase, it rises in the basal layer on 6th day, but on 9th day it is the same as on 3rd day. The autoradiographical analysis showed that the activity of RNA synthesis in cells of the surface epithel is of rising tendency from 3rd to 9th day The intensity of RNA synthesis in functional zone does not change during the early lutheal phase, it rises in the basal layer on 6th day, but on 9th day it is the same as on 3rd day. The glycoproteins are synthetised mainly by the Golgi apparatus in supranuclear sphere in the cells of surface epithel and in glandular cells. The glycoproteins were not observed in apical regions of cells on 3rd day of cycle, however, they are intensively

Anticoagulation therapy a risk factor for the development of chronic subdural hematoma

DEFF Research Database (Denmark)

Aspegren, Oskar P.; Åstrand, Ramona; Lundgren, Maria I.

2013-01-01

Chronic subdural hematoma (CSDH) is a common disease among the elderly and with increasing incidence we have chosen to focus on associations between development and recurrence of CSDH and anticoagulation and/or antiplatelet agent therapy.......Chronic subdural hematoma (CSDH) is a common disease among the elderly and with increasing incidence we have chosen to focus on associations between development and recurrence of CSDH and anticoagulation and/or antiplatelet agent therapy....

Bioassay-guided fractionation of Melastoma malabathricum Linn. leaf solid phase extraction fraction and its anticoagulant activity.

Science.gov (United States)

Khoo, Li Teng; Abdullah, Janna Ong; Abas, Faridah; Tohit, Eusni Rahayu Mohd; Hamid, Muhajir

2015-02-24

The aims of this study were to examine the bioactive component(s) responsible for the anticoagulant activity of M. malabathricum Linn. leaf hot water crude extract via bioassay-guided fractionation and to evaluate the effect of bioactive component(s) on the intrinsic blood coagulation pathway. The active anticoagulant fraction of F3 was subjected to a series of chromatographic separation and spectroscopic analyses. Furthermore, the effect of the bioactive component(s) on the intrinsic blood coagulation pathway was studied through immediate and time incubation mixing studies. Through Activated Partial Thromboplastin Time (APTT) assay-guided fractionation, Subfraction B was considered the most potent anticoagulant fraction. Characterisation of Subfraction B indicated that anticoagulant activity could partly be due to the presence of cinnamic acid and a cinnamic acid derivative. APTT assays for both the immediate and time incubation mixing were corrected back into normal clotting time range (35.4-56.3 s). In conclusion, cinnamic acid and cinnamic acid derivative from Subfraction B were the first such compounds to be discovered from M. malabathricum Linn. leaf hot water crude extract that possess anticoagulant activity. This active anticoagulant Subfraction B prolonged blood clotting time by causing factor(s) deficiency in the intrinsic blood coagulation pathway.

Physicochemical properties and anticoagulant activity of polyphenols derived from Lachnum singerianum

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Shuai Zong

2017-10-01

Full Text Available In this study, polyphenols (LSP were obtained from the fermentation broth of Lachnum singerianum. Two fractions were isolated by Sephadex LH-20 chromatographic column, and the primary fraction (LSP-1 was collected. The comprehensive physicochemical properties of phenolic acids and polyhydroxy phenolic compounds of LSP-1 were determined by UV-visible spectroscopy, Fourier transform infrared spectroscopy, and gas chromatography–mass spectrometry. Results of anticoagulant activity assay in vitro showed that LSP-1 could lengthen prothrombin time, activated partial thromboplastin time, and thrombin time of mouse plasma. In addition, anticoagulant activity results in vivo showed that high dose of LSP-1 could significantly prolong bleeding time, coagulation time, prothrombin time, activated partial thromboplastin time, and thrombin time of hypercoagulable mice induced by adrenaline, reduce the content of fibrinogen and enhance antithrombin III activity. All results indicated that the LSP-1 could serve well as an anticoagulant, and might be used as a potential natural drug candidate for thrombosis.

Glycoprotein cytoplasmic domain sequences required for rescue of a vesicular stomatitis virus glycoprotein mutant

International Nuclear Information System (INIS)

Whitt, M.A.; Chong, L.; Rose, J.K.

1989-01-01

The authors have used transient expression of the wild-type vesicular stomatitis virus (VSV) glycoprotein (G protein) from cloned cDNA to rescue a temperature-sensitive G protein mutant of VSV in cells at the nonpermissive temperature. Using cDNAs encoding G proteins with deletions in the normal 29-amino-acid cytoplasmic domain, they determined that the presence of either the membrane-proximal 9 amino acids or the membrane-distal 12 amino acids was sufficient for rescue of the temperature-sensitive mutant. G proteins with cytoplasmic domains derived from other cellular or viral G proteins did not rescue the mutant, nor did G proteins with one or three amino acids of the normal cytoplasmic domain. Rescue correlated directly with the ability of the G proteins to be incorporated into virus particles. This was shown by analysis of radiolabeled particles separated on sucrose gradients as well as by electron microscopy of rescued virus after immunogold labeling. Quantitation of surface expression showed that all of the mutated G proteins were expressed less efficiently on the cell surface than was wild-type G protein. However, they were able to correct for differences in rescue efficiency resulting from differences in the level of surface expression by reducing wild-type G protein expression to levels equivalent to those observed for the mutated G proteins. The results provide evidence that at least a portion of the cytoplasmic domain is required for efficient assembly of the VSV G protein into virions during virus budding

Regulation of glycoprotein synthesis in yeast by mating pheromones

International Nuclear Information System (INIS)

Tanner, W.

1984-01-01

In Saccharomyces cerevisiae, glycosylated proteins amount to less than 2% of the cell protein. Two intensively studied examples of yeast glycoproteins are the external cell wall - associated invertase and the vacuolar carboxypeptidase Y. Recently, it was shown that the mating pheromone, alpha factor, specifically and strongly inhibits the synthesis of N-glycosylated proteins in haploid a cells, whereas O-glycosylated proteins are not affected. In this paper, the pathways of glycoprotein biosynthesis are summarized briefly, and evidence is presented that mating pheomones have a regulatory function in glycoprotein synthesis

Engineered CHO cells for production of diverse, homogeneous glycoproteins

DEFF Research Database (Denmark)

Yang, Zhang; Wang, Shengjun; Halim, Adnan

2015-01-01

Production of glycoprotein therapeutics in Chinese hamster ovary (CHO) cells is limited by the cells' generic capacity for N-glycosylation, and production of glycoproteins with desirable homogeneous glycoforms remains a challenge. We conducted a comprehensive knockout screen of glycosyltransferas...

Bioinformatics Analysis of Envelope Glycoprotein E epitopes of ...

African Journals Online (AJOL)

The E glycoprotein of dengue virus is responsible for the viral binding to the receptor. The crystal structure of envelope glycoprotein has already been determined. However, where the well-defined Bcell and T-cell epitopes are located is still a question. Because of the large variations among the four dengue genotypes, it is ...

The Purification of a Blood Group A Glycoprotein: An Affinity Chromatography Experiment.

Science.gov (United States)

Estelrich, J.; Pouplana, R.

1988-01-01

Describes a purification process through affinity chromatography necessary to obtain specific blood group glycoproteins from erythrocytic membranes. Discusses the preparation of erythrocytic membranes, extraction of glycoprotein from membranes, affinity chromatography purification, determination of glycoproteins, and results. (CW)

Oral anticoagulation for stroke prevention amongst atrial fibrillation patients with valvular heart disease: an update.

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Ha, Andrew C T; Verma, Atul; Verma, Subodh

2017-03-01

The majority of evidence on the safety and efficacy of oral anticoagulation for stroke prevention amongst patients with atrial fibrillation is derived from those without significant valvular heart disease. This article will review current knowledge, areas of uncertainty and controversy, and ongoing research on oral anticoagulation for stroke prevention amongst patients with valvular heart disease. The rates of stroke, systemic embolism, and major bleeding were similar for patients with and without significant native valvular disease when treated with direct oral anticoagulants (DOACs) or vitamin K antagonists. There are very limited prospective data on the safety and efficacy of DOAC use for patients with bioprosthetic valves or rheumatic mitral stenosis. Atrial fibrillation patients with concomitant valvulopathies constitute a group with high thromboembolic risk and should be treated with oral anticoagulation. There is good supportive evidence that DOAC is well tolerated and effective in preventing thromboembolism amongst patients with native valvular disease. Further research is underway to better define the risks and benefits of DOAC use among patients with bioprosthetic valves or rheumatic mitral stenosis in preventing thromboembolic events. Until then, vitamin K antagonists remain the oral anticoagulant of choice for these patient subsets.

Blocking variant surface glycoprotein synthesis alters endoplasmic reticulum exit sites/Golgi homeostasis in Trypanosoma brucei.

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Ooi, Cher-Pheng; Smith, Terry K; Gluenz, Eva; Wand, Nadina Vasileva; Vaughan, Sue; Rudenko, Gloria

2018-06-01

The predominant secretory cargo of bloodstream form Trypanosoma brucei is variant surface glycoprotein (VSG), comprising ~10% total protein and forming a dense protective layer. Blocking VSG translation using Morpholino oligonucleotides triggered a precise pre-cytokinesis arrest. We investigated the effect of blocking VSG synthesis on the secretory pathway. The number of Golgi decreased, particularly in post-mitotic cells, from 3.5 ± 0.6 to 2.0 ± 0.04 per cell. Similarly, the number of endoplasmic reticulum exit sites (ERES) in post-mitotic cells dropped from 3.9 ± 0.6 to 2.7 ± 0.1 eight hours after blocking VSG synthesis. The secretory pathway was still functional in these stalled cells, as monitored using Cathepsin L. Rates of phospholipid and glycosylphosphatidylinositol-anchor biosynthesis remained relatively unaffected, except for the level of sphingomyelin which increased. However, both endoplasmic reticulum and Golgi morphology became distorted, with the Golgi cisternae becoming significantly dilated, particularly at the trans-face. Membrane accumulation in these structures is possibly caused by reduced budding of nascent vesicles due to the drastic reduction in the total amount of secretory cargo, that is, VSG. These data argue that the total flux of secretory cargo impacts upon the biogenesis and maintenance of secretory structures and organelles in T. brucei, including the ERES and Golgi. © 2018 The Authors. Traffic published by John Wiley & Sons Ltd.

INR targets and site-level anticoagulation control: results from the Veterans AffaiRs Study to Improve Anticoagulation (VARIA).

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Rose, A J; Berlowitz, D R; Miller, D R; Hylek, E M; Ozonoff, A; Zhao, S; Reisman, J I; Ash, A S

2012-04-01

Not all clinicians target the same International Normalized Ratio (INR) for patients with a guideline-recommended target range of 2-3. A patient's mean INR value suggests the INR that was actually targeted. We hypothesized that sites would vary by mean INR, and that sites of care with mean values nearest to 2.5 would achieve better anticoagulation control, as measured by per cent time in therapeutic range (TTR). To examine variations among sites in mean INR and the relationship with anticoagulation control in an integrated system of care. We studied 103,897 patients receiving oral anticoagulation with an expected INR target between 2 and 3 at 100 Veterans Health Administration (VA) sites from 1 October 2006 to 30 September 2008. Key site-level variables were: proportion near 2.5 (that is, percentage of patients with mean INR between 2.3 and 2.7) and mean risk-adjusted TTR. Site mean INR ranged from 2.22 to 2.89; proportion near 2.5, from 30 to 64%. Sites' proportions of patients near 2.5, below 2.3 and above 2.7 were consistent from year to year. A 10 percentage point increase in the proportion near 2.5 predicted a 3.8 percentage point increase in risk-adjusted TTR (P < 0.001). Proportion of patients with mean INR near 2.5 is a site-level 'signature' of care and an implicit measure of targeted INR. This proportion varies by site and is strongly associated with site-level TTR. Our study suggests that sites wishing to improve TTR, and thereby improve patient outcomes, should avoid the explicit or implicit pursuit of non-standard INR targets. © 2012 International Society on Thrombosis and Haemostasis.

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

DEFF Research Database (Denmark)

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

2008-01-01

Anticoagulant resistance in Norway rats (Rattus norvegicus) has been suggested to be due to mutations in the VKORC1 gene, encoding the target protein of anticoagulant rodenticides such as warfarin and bromadiolone. Other factors, e.g. pharmacokinetics, may however also contribute to resistance. We...... that bromadiolone resistance in Norway rats involves enhanced anticoagulant clearance and metabolism catalyzed by specific cytochrome P450 enzymes, such as Cyp2e1, Cyp3a2 and Cyp3a3. This pharmacokinetically based resistance varies to some extend between the genders....

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

DEFF Research Database (Denmark)

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

2008-01-01

Background: Anticoagulant resistance in Norway rats, Rattus norvegicus (Berk.), has been suggested to be conferred by mutations in the VKORC1 gene, encoding the target protein of anticoagulant rodenticides. Other factors, e.g. pharmacokinetics, may also contribute to resistance, however. To examine......, Cyp3a2 and Cyp3a3 genes. On exposure to bromadiolone, females had higher Cyp2e1 expression than males, which possibly explains why female rats are generally more tolerant to anticoagulants than male rats. Conclusion: results suggest that bromadiolone resistance in a Danish strain of Norway rats...

Characterization and endocytic internalization of Epith-2 cell surface glycoprotein during the epithelial-to-mesenchymal transition in sea urchin embryos

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Norio eWakayama

2013-08-01

Full Text Available The epithelial cells of the sea urchin Hemicentrotus pulcherrimus embryo express an Epith-2, uncharacterized glycoprotein, on the lateral surface. Here, we describe internalization of Epith-2 during mesenchyme formation through the epithelial-to-mesenchymal transition (EMT. Epith-2 was first expressed on the entire egg surface soon after fertilization and on the blastomeres until the 4-cell stage, but was localized to the lateral surface of epithelial cells at and after the 16-cell stage throughout the later developmental period. However, primary (PMC and secondary mesenchyme cells (SMC that ingress by EMT lost Epith-2 from their cell surface by endocytosis during dissociation from the epithelium, which was associated with the appearance of cytoplasmic Epith-2 dots. The cytoplasmic Epith-2 retained a similar relative molecular mass to that of the cell surface immediately after ingression through the early period of the spreading to single cells. Then, Epith-2 was completely lost from the cytoplasm. Tyrosine residues of Epith-2 were phosphorylated. The endocytic retraction of Epith-2 was inhibited by herbimycin A (HA, a protein tyrosine kinase (PTK inhibitor, and suramin, a growth factor receptor (GFR inhibitor, suggesting the involvement of the GFR/PTK (GP signaling pathway. These two GP inhibitors also inhibited PMC and SMC spreading to individual cells after ingression, but the dissociation of PMC and SMC from the epithelium was not inhibited. In suramin-treated embryos, dissociated mesenchyme cells migrated partially by retaining their epithelial morphology. In HA-treated embryos, no mesenchyme cells migrated. Thus, the EMT occurs in relation to internalization of Epith-2 from presumptive PMC and SMC.

Glycan Reader: Automated Sugar Identification and Simulation Preparation for Carbohydrates and Glycoproteins

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Jo, Sunhwan; Song, Kevin C.; Desaire, Heather; MacKerell, Alexander D.; Im, Wonpil

2011-01-01

Understanding how glycosylation affects protein structure, dynamics, and function is an emerging and challenging problem in biology. As a first step toward glycan modeling in the context of structural glycobiology, we have developed Glycan Reader and integrated it into the CHARMM-GUI, http://www.charmm-gui.org/input/glycan. Glycan Reader greatly simplifies the reading of PDB structure files containing glycans through (i) detection of carbohydrate molecules, (ii) automatic annotation of carbohydrates based on their three-dimensional structures, (iii) recognition of glycosidic linkages between carbohydrates as well as N-/O-glycosidic linkages to proteins, and (iv) generation of inputs for the biomolecular simulation program CHARMM with the proper glycosidic linkage setup. In addition, Glycan Reader is linked to other functional modules in CHARMM-GUI, allowing users to easily generate carbohydrate or glycoprotein molecular simulation systems in solution or membrane environments and visualize the electrostatic potential on glycoprotein surfaces. These tools are useful for studying the impact of glycosylation on protein structure and dynamics. PMID:21815173

The Mycobacterium tuberculosis cell-surface glycoprotein apa as a potential adhesin to colonize target cells via the innate immune system pulmonary C-type lectin surfactant protein A.

Science.gov (United States)

Ragas, Aude; Roussel, Lucie; Puzo, Germain; Rivière, Michel

2007-02-23

Tuberculosis is still a major health problem, and understanding the mechanism by which Mycobacterium tuberculosis (Mtb) invades and colonizes its host target cells remains an important issue for the control of infection. The innate immune system C-type lectins (C-TLs), including the human pulmonary surfactant protein A (PSP-A), have been recently identified as determinant players in the early recognition of the invading pathogen and in mounting the host defense response. Although the antigenic lipoglycan mannosylated lipoarabinomannan is currently considered to be the major C-TL target on the mycobacterial surface, the recognition by some C-TLs of the only mycobacterial species composing the "Mtb complex" indicates that mannosylated lipoarabinomannan cannot account alone for this specificity. Thus, we searched for the mycobacterial molecules targeted by human PSP-A, focusing our attention on the Mtb surface glycoproteins. We developed an original functional proteomic approach based on a lectin blot assay using crude human bronchoalveolar lavage fluid as a source of physiological PSP-A. Combined with selective cell-surface protein extraction and mass spectrometry peptide mapping, this strategy allowed us to identify the Apa (alanine- and proline-rich antigenic) glycoprotein as new potential target for PSP-A. This result was supported by direct binding of PSP-A to purified Apa. Moreover, EDTA addition or deglycosylation of purified Apa samples completely abolished the interaction, demonstrating that the interaction is calcium- and mannose-dependent, as expected. Finally, we provide convincing evidence that Apa, formerly considered as mainly secreted, is associated with the cell wall for a sufficiently long time to aid in the attachment of PSP-A. Because, to date, Apa seems to be restricted to the Mtb complex strains, we propose that it may account for the selective recognition of those strains by PSP-A and other immune system C-TLs containing homologous functional

Impact of Anticoagulation in Elderly Patients With Pulmonary Embolism That Undergo IVC Filter Placement: A Retrospective Cohort Study.

Science.gov (United States)

Falatko, John M; Dalal, Bhavinkumar; Qu, Lihua

2017-12-01

Anticoagulation is the primary treatment for pulmonary embolism (PE). Inferior vena cava (IVC) filters are an adjunctive intervention to prevent recurrent pulmonary embolism. Long-term outcomes in elderly patients with contraindications to anticoagulation after IVC filter placement for prevention of recurrent pulmonary embolism have yet to be assessed. Patients ≥60years of age, that had an IVC filter placed between 1 January, 2008 and 2 February, 2013, with a primary diagnosis of pulmonary embolism, were included. Patients that died during index hospitalisation, were discharged to hospice, or had active malignancy were excluded. The primary endpoint was overall survival. Patients were divided depending on whether they were treated with an approved anticoagulant for VTE or had no anticoagulant. Of the 152 patients identified, 55 were not anti-coagulated after IVC filter placement. The incidence of death was 0.4 per 1000 filter days and 0.7 per 1000 filter days in the anti-coagulated and untreated groups respectively (p-value=0.06). After statistical correction for co-morbid conditions, the effect of anticoagulation was not significant (HR 0.82 CI 0.49-1.37, p-value 0.46). Age was a significant confounder that was associated with death. Increased BMI was protective. Indications for IVC filter placement were numerous, but similar between the two groups. Treatment with an approved anticoagulant is recommended after IVC filter placement for prevention of recurrent PE, however its effect may be attenuated by advanced age. In elderly patients that have undergone IVC filter placement for prevention of recurrent PE, survival may be more dependent on age and co-morbid conditions than exposure to anticoagulation. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

[Anticoagulation in the aged patient with atrial fibrillation: What are prescribing cardiologists, geriatricians and general practitioners?].

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Fuchs, P; Vogel, T; Lang, P-O

2015-08-01

To assess prescribing of anticoagulants in atrial fibrillation (AF) in the elderly, both a quantitative point of view (rate of anticoagulation) and qualitative (type of anticoagulation). Determinants of prescribing and non-prescribing were also analysed. Prospective survey of practice, based on one clinical case and questionnaire conducted in 60 practitioners (20 cardiologists [C], 20 geriatricians [G] and 20 general practitioners [GP]). In reading the clinical case, 88.3% of physicians would have initiated a treatment; three types of treatments would have been chosen: AVK (68.3%), ODA (20.0%) and platelet antiaggregant (11.7%). Criteria taken into account to initiate anticoagulation varied according to the specialty. Cardiologists considered more the age criteria (C: 95.0%, G: 75.0%, MG: 60.0%; PC: 90.0%, G: 60.0%, MG: 55.0%; PC: 85.0%, G: 55.0%, MG: 60.0%; PC: 80.0%, G: 35.0%, MG: 25.0%; PC: 15.0%, G: 5.0%, MG: 0.0%; PC: 35.0%, G: 5.0%, MG: 45.0%; PC: 70.0%, G: 75.0%, MG: 85.0%; P<0.05). This survey confirms that the FA remains under anticoagulated in the elderly and the barriers to the prescription of oral anticoagulation are often without rational basis. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

The inositol-1,2-cyclic phosphate moiety of the cross-reacting determinant, carbohydrate chains, and proteinaceous components are all responsible for the cross-reactivity of trypanosome variant surface glycoproteins.

Science.gov (United States)

Escalona, José L; Uzcanga, Graciela L; Carrasquel, Liomary M; Bubis, José

2018-01-24

Salivarian trypanosomes evade the host immune system by continually swapping their protective variant surface glycoprotein (VSG) coat. Given that VSGs from various trypanosome stocks exhibited cross-reactivity (Camargo et al., Vet. Parasitol. 207, 17-33, 2015), we analyzed here which components are the antigenic determinants for this cross-reaction. Soluble forms of VSGs were purified from four Venezuelan animal trypanosome isolates: TeAp-N/D1, TeAp-ElFrio01, TeAp-Mantecal01, and TeGu-Terecay323. By using the VSG soluble form from TeAp-N/D1, we found that neither the inositol-1,2-cyclic phosphate moiety of the cross-reacting determinant nor the carbohydrate chains were exclusively responsible for its cross-reactivity. Then, all four purified glycoproteins were digested with papain and the resulting peptides were separated by high-performance liquid chromatography. Dot blot evaluation of the fractions using sera from trypanosome-infected animals yielded peptides that possessed cross-reaction activity, demonstrating for the first time that proteinaceous epitopes are also responsible for the cross-reactivity of trypanosome VSGs.

Quality of Life analysis of patients in chronic use of oral anticoagulant: an observational study

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Almeida Geisa

2011-10-01

Full Text Available Abstract Background Treatment with oral anticoagulant may influence the quality of life perception as it promotes changes in the patient's life, not offering an evident symptomatic relief and presenting well defined risks, such as bleeding. In this trial, the influence of chronic use of anticoagulants on the quality of life perception has been analyzed in patients assisted at the anticoagulation outpatient unit. Methods The health related quality of life was evaluated through a cross-section study with a sample composed of 72 patients seen from July 23, 2009 to September 2, 2010 at the Anticoagulation Outpatient Unit of the Federal University of Bahia's University Hospital. The study's population was composed by patients with atrial fibrillation and mechanical heart valve. The patients were submitted to two quality of life evaluation questionnaires: a generic questionnaire - the Medical Outcomes Study SF-36 Health Survey (SF36 - and a specific questionnaire - the Duke Anticoagulation Satisfaction Scale (DASS. Results The quality of life perception of the patients studied, based on both the DASS and the SF36, was positive regarding the treatment with oral anticoagulant. The SF36 presented an average score of 62.2 (± 20.0. Among the SF36 evaluated domains, the physical-emotional aspect was the most compromised one regarding life quality perception. The DASS presented an average score of 67.1 (± 18.2 and the domain presenting a greater compromise was the one related to the treatment inconveniences (annoyances, burdens and obligations. Previous hemorrhagic event, comorbidities, drug interactions with medicines that increase the anticoagulant effect, lower education level in the SF36 and younger age group influence a more negative perception of the quality of life, whereas lower education level in the DASS and the duration of treatment for more than 1 year offer a more positive perception. Conclusion Patients seen at the anticoagulation outpatient

Partial Purification and Characterization of Anticoagulant Factor from the Snake (Echis Carinatus) Venom

Science.gov (United States)

Amrollahi Byoki, Elham; Zare Mirakabadi, Abbas

2013-01-01

Objective(s): Snake venoms contain complex mixture of proteins with biological activities. Some of these proteins affect blood coagulation and platelet function in different ways. Snake venom toxin may serve as a starting material for drug design to combat several pathophysiological problems such as cardiovascular disorders. In the present study, purification of anticoagulation factor from venom of snake (Echis carinatus) was studied. Materials and Methods: Anticoagulation activity of crude venom, fractions and purified peptide were determined by using prothrombin time (PT) and thrombin time (TT). Three fractions were partially purified from the venom of E. Carinatus by gel filtration on sephadex G-75 and final purification was performed by high-performance liquid chromatography (HPLC) with C18 column. A purified anticoagulant factor was derived which showed a single protein band in SDS-PAGE electrophoresis under reducing condition. Results: Results of PT and TT tests for purified peptide (EC217) were found to be 102±4.242 and < 5 min. respectively. Determination of molecular weight revealed that the active purified peptide (EC217) was about 30 KD. Conclusion: The present study showed that the venom of E. carinatus contains at least one anticoagulant factor. PMID:24494065

Partial Purification and Characterization of Anticoagulant Factor from the Snake (Echis carinatus Venom

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Elham Amrollahi Byoki

2013-11-01

Full Text Available   Objective(s: Snake venoms contain complex mixture of proteins with biological activities. Some of these proteins affect blood coagulation and platelet function in different ways. Snake venom toxin may serve as a starting material for drug design to combat several pathophysiological problems such as cardiovascular disorders. In the present study, purification of anticoagulation factor from venom of snake (Echis carinatus was studied. Anticoagulation activity of crude venom, fractions and purified peptide were determined by using prothrombin time (PT and thrombin time (TT. Three fractions were partially purified from the venom of E. Carinatus by gel filtration on sephadex G-75 and final purification was performed by high-performance liquid chromatography (HPLC with C18 column. A purified anticoagulant factor was derived which showed a single protein band in SDS-PAGE electrophoresis under reducing condition. Results of PT and TT tests for purified peptide (EC217 were found to be 102±4.242 and < 5 min. respectively. Determination of molecular weight revealed that the active purified peptide (EC217 was about 30 KD. In conclusion, the present study showed that the venom of E. carinatus contains at least one anticoagulant factor.

Structure and anticoagulant activity of a sulfated galactan from the red alga, Gelidium crinale. Is there a specific structural requirement for the anticoagulant action?

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Pereira, Maria G; Benevides, Norma M B; Melo, Marcia R S; Valente, Ana Paula; Melo, Fábio R; Mourão, Paulo A S

2005-09-05

Marine red algae are an abundant source of sulfated galactans with potent anticoagulant activity. However, the specific structural motifs that confer biological activity remain to be elucidated. We have now isolated and purified a sulfated galactan from the marine red alga, Gellidium crinale. The structure of this polysaccharide was determined using NMR spectroscopy. It is composed of the repeating structure -4-alpha-Galp-(1-->3)-beta-Galp1--> but with a variable sulfation pattern. Clearly 15% of the total alpha-units are 2,3-di-sulfated and another 55% are 2-sulfated. No evidence for the occurrence of 3,6-anhydro alpha-galactose units was observed in the NMR spectra. We also compared the anticoagulant activity of this sulfated galactan with a polysaccharide from the species, Botryocladia occidentalis, with a similar saccharide chain but with higher amounts of 2,3-di-sulfated alpha-units. The sulfated galactan from G. crinale has a lower anticoagulant activity on a clotting assay when compared with the polysaccharide from B. occidentalis. When tested in assays using specific proteases and coagulation inhibitors, these two galactans showed significant differences in their activity. They do not differ in thrombin inhibition mediated by antithrombin, but in assays where heparin cofactor II replaces antithrombin, the sulfated galactan from G. crinale requires a significantly higher concentration to achieve the same inhibitory effect as the polysaccharide from B. occidentalis. In contrast, when factor Xa instead of thrombin is used as the target protease, the sulfated galactan from G. crinale is a more potent anticoagulant. These observations suggest that the proportion and/or the distribution of 2,3-di-sulfated alpha-units along the galactan chain may be a critical structural motif to promote the interaction of the protease with specific protease and coagulation inhibitors.

Isolation and characterization of two antigenic glycoproteins from the pollen of Prosopis juliflora.

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Thakur, I S

1991-03-01

Two antigenically active glycoprotein fractions were isolated from crude extract of the pollen of Prosopis juliflora using DEAE-cellulose ion exchange chromatography. The glycoproteins gave single band on polyacrylamide gel electrophoresis. The molecular weight of these two glycoprotein was 20,000 and 10,000 as determined by gel filtration on Sephadex G-75. With the help of crossed immunoelectrophoresis and gel diffusion crude extract exhibited twelve and three precipitating antigens suggesting its heterogeneous nature; and the purified glycoprotein fractions however formed single precipitin band on gel diffusion test and immunoelectrophoresis. As tested by ELISA the polyclonal antisera raised in rabbit showed strong binding affinity with glycoprotein of MW 20,000. These result indicates that the two glycoprotein fractions are not antigenically identical.

Synthesis and biological activity of the novel indanedione anticoagulant rodenticides containing fluorine

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Chen, Feng; Liu, Liping; Bai, Zengguo; Zhang, Tianhua; Zhao, Keke

2016-01-01

Here, 3 fluorinated intermediates of drug were synthesized: (M1), (M2), (M3). Three new anticoagulant rodenticides were designed which were based on 4-hydroxycoumarin or 1,3-indandione, added acute toxicity groups containing fluorine. The structures of synthesized compounds were analyzed and proved by FT-IR spectroscopy and 1H nuclear magnetic resonance (1H-NMR). The compounds were also evaluated for their anticoagulant and acute biologic activity. In addition, both the acute orally toxicity ...

Sulfated modification and anticoagulant activity of pumpkin (Cucurbita pepo, Lady Godiva) polysaccharide.

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Liang, Li; Ao, Le; Ma, Tao; Ni, Yuanying; Liao, Xiaojun; Hu, Xiaosong; Song, Yi

2018-01-01

Sulfated modification of pumpkin polysaccharide using CAS with pyridines as catalysts under different conditions was conducted to obtain different degrees of sulfation on a laboratory scale. Anticoagulant activities of pumpkin polysaccharide and its sulfated derivatives were also investigated employing various established in vitro systems. Results showed that addition of high ratio of CAS/pyridine under constant conditions could increase the degree of substitution. Sulfate substitution was further confirmed by the FT-IR and 13 C NMR analysis. The d f values between 2.11-2.73 indicated the relatively expanded conformation of the sulfated derivatives. The sulfated polysaccharides showed higher anticoagulant activities through activated partial thrombosis time (aPTT), thrombin time (TT), prothrombin time (PT) and anti-Xa activity assay, which revealed that better anticoagulant activities could be obtained when DS remained higher and M w maintained in a moderate range. Copyright © 2017 Elsevier B.V. All rights reserved.

Cost Effectiveness of Implantable Cardiac Monitor-Guided Intermittent Anticoagulation for Atrial Fibrillation: An Analysis of the REACT.COM Pilot Study.

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Steinhaus, Daniel A; Zimetbaum, Peter J; Passman, Rod S; Leong-Sit, Peter; Reynolds, Matthew R

2016-08-30

Anticoagulation guidelines for patients with atrial fibrillation (AF) disregard AF burden. A strategy of targeted anticoagulation with novel oral anticoagulants (NOACs) based on continuous rhythm assessment with an implantable cardiac monitor (ICM) has recently been explored. We evaluated the potential cost-effectiveness of this strategy versus projected outcomes with continuous anticoagulation. We developed a Markov model using data from the Rhythm Evaluation for AntiCoagulaTion With COntinuous Monitoring (REACT.COM) pilot study (N = 59) and prior NOAC trials to calculate the costs and quality-adjusted life years (QALYs) associated with ICM-guided intermittent anticoagulation for AF versus standard care during a 3-year time horizon. Health state utilities were estimated from the pilot study population using the SF-12. Costs were based on current Medicare reimbursement. Over 14 ± 4 months of follow-up, 18 of 59 patients had 35 AF episodes. The ICM-guided strategy resulted in a 94% reduction in anticoagulant use relative to continuous treatment. There were no strokes, 3 (5.1%) TIAs, 2 major bleeding events (on aspirin) and 3 minor bleeding events with the ICM-guided strategy. The projected total 3-year costs were $12,535 for the ICM-guided strategy versus $13,340 for continuous anticoagulation. Projected QALYs were 2.45 for both groups. Based on a pilot study, a strategy of ICM-guided anticoagulation with NOACs may be cost-saving relative to expected outcomes with continuous anticoagulation, with similar quality-adjusted survival. This strategy could be attractive from a health economic perspective if shown to be safe and effective in a rigorous clinical trial. © 2016 Wiley Periodicals, Inc.

Impact of INR monitoring, reversal agent use, heparin bridging, and anticoagulant interruption on rebleeding and thromboembolism in acute gastrointestinal bleeding.

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Naoyoshi Nagata

Full Text Available Anticoagulant management of acute gastrointestinal bleeding (GIB during the pre-endoscopic period has not been fully addressed in American, European, or Asian guidelines. This study sought to evaluate the risks of rebleeding and thromboembolism in anticoagulated patients with acute GIB.Baseline, endoscopy, and outcome data were reviewed for 314 patients with acute GIB: 157 anticoagulant users and 157 age-, sex-, and important risk-matched non-users. Data were also compared between direct oral anticoagulants (DOACs and warfarin users.Between anticoagulant users and non-users, of whom 70% underwent early endoscopy, no endoscopy-related adverse events or significant differences were found in the rate of endoscopic therapy need, transfusion need, rebleeding, or thromboembolism. Rebleeding was associated with shock, comorbidities, low platelet count and albumin level, and low-dose aspirin use but not HAS-BLED score, any endoscopic results, heparin bridge, or international normalized ratio (INR ≥ 2.5. Risks for thromboembolism were INR ≥ 2.5, difference in onset and pre-endoscopic INR, reversal agent use, and anticoagulant interruption but not CHA2DS2-VASc score, any endoscopic results, or heparin bridge. In patients without reversal agent use, heparin bridge, or anticoagulant interruption, there was only one rebleeding event and no thromboembolic events. Warfarin users had a significantly higher transfusion need than DOACs users.Endoscopy appears to be safe for anticoagulant users with acute GIB compared with non-users. Patient background factors were associated with rebleeding, whereas anticoagulant management factors (e.g. INR correction, reversal agent use, and drug interruption were associated with thromboembolism. Early intervention without reversal agent use, heparin bridge, or anticoagulant interruption may be warranted for acute GIB.

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

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Zolfagharian, Hossein; Mohajeri, Mohammad; Babaie, Mahdi

2015-12-01

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

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

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Hossein Zolfagharian

2015-12-01

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

Effective management of venous thromboembolism in the community: non-vitamin K antagonist oral anticoagulants

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Patel R

2016-05-01

Full Text Available Raj Patel Department of Haematological Medicine, King's Thrombosis Centre, King's College Hospital, London, UK Abstract: Anticoagulation therapy is essential for the effective treatment and secondary prevention of venous thromboembolism (VTE. For many years, anticoagulation for acute VTE was limited to the use of initial parenteral heparin, overlapping with and followed by a vitamin K antagonist. Although highly effective, this regimen has several limitations and is particularly challenging when given in an ambulatory setting. Current treatment pathways for most patients with deep-vein thrombosis typically involve initial hospital or community-based ambulatory care with subsequent follow-up in a secondary care setting. With the introduction of non-vitamin K antagonist oral anticoagulants (NOACs into routine clinical practice, it is now possible for the initial acute management of patients with deep-vein thrombosis to be undertaken by primary care. As hospital admissions associated with VTE become shorter, primary care will play an increasingly important role in the long-term management of these patients. Although the NOACs can potentially simplify patient management and improve clinical outcomes, primary care physicians may be less familiar with these new treatments compared with traditional therapy. To assist primary care physicians in further understanding the role of the NOACs, this article outlines the main differences between NOACs and traditional anticoagulation therapy and discusses the benefit–risk profile of the different NOACs in the treatment and secondary prevention of recurrent VTE. Key considerations for the use of NOACs in the primary care setting are highlighted, including dose transition, risk assessment and follow-up, duration of anticoagulant therapy, how to minimize bleeding risks, and the importance of patient education and counseling. Keywords: venous thromboembolism, oral anticoagulant, prevention, treatment, primary

Lupus anticoagulant-hypoprothrombinemia syndrome and catastrophic antiphospholipid syndrome in a patient with antidomain I antibodies.

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Galland, Joris; Mohamed, Shirine; Revuz, Sabine; de Maistre, Emmanuel; de Laat, Bas; Marie, Pierre-Yves; Zuily, Stéphane; Lévy, Bruno; Regnault, Véronique; Wahl, Denis

2016-07-01

Lupus anticoagulant-hypoprothrombinemia syndrome is a rare condition characterized by the association of acquired factor II deficiency and lupus anticoagulant. Contrary to classical antiphospholipid syndrome, it may cause severe life-threatening bleeding (89% of published cases). We report a patient, positive for antidomain I antibodies, with initially primary lupus anticoagulant-hypoprothrombinemia syndrome without previous clinical manifestation or underlying systemic disease. Five years later, he experienced the first systemic lupus erythematous flare. Within a few days, catastrophic antiphospholipid syndrome was diagnosed with heart, liver and kidney involvement. The patient recovered under pulse steroids, intravenous heparin and intravenous immunoglobulins.

Purification and characterization of the glycoprotein allergen from Prosopis juliflora pollen.

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Thakur, I S

1991-02-01

Highly active glycoprotein allergens have been isolated from pollen of Prosopis juliflora by a combination of Sephadex G-100 gel filtration and Sodium dodecyl sulphate-Poly-acrylamide gel electrophoresis. The glycoprotein fraction was homogeneous, and had molecular weight 20,000. The purified glycoprotein allergen contained 20% carbohydrate, mainly arabinose and galactose. Enzymatic digestion of glycoprotein with protease released glycopeptides of molecular weight ranging from less than 1,000 to more than 5,000 on Sephadex G-25 gel filtration. Antigenicity or allergenicity testing of these glycopeptides by immunodiffusion, immunoelectrophoresis, and radioallergosorbent test indicated complete loss of allergenic activity after digestion with protease whereas incubation with beta-D-galactosidase and periodate oxidation had little affect on the allergenic activity of the glycoprotein fraction. But incubation with alpha-D-glucosidase did not affect the allergenic activity significantly. All these tests indicated that protein played significant role in allergenicity of P. juliflora pollen.

Anticoagulant Effect of Sugammadex: Just an In Vitro Artifact.

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Dirkmann, Daniel; Britten, Martin W; Pauling, Henning; Weidle, Juliane; Volbracht, Lothar; Görlinger, Klaus; Peters, Jürgen

2016-06-01

Sugammadex prolongs activated partial thromboplastin time (aPTT) and prothrombin time (PT) suggestive of anticoagulant effects. To pinpoint its presumed anticoagulant site of action, the authors assessed Sugammadex's impact on a panel of coagulation assays. Sugammadex, Rocuronium, Sugammadex and Rocuronium combined, or saline were added to blood samples from healthy volunteers and analyzed using plasmatic (i.e., aPTT, thrombin time, and fibrinogen concentration) (n = 8 each), PT (quick), activities of plasmatic coagulation factors, and whole blood (extrinsically and intrinsically activated thromboelastometry) assays (n = 18 each). Furthermore, dose-dependent effects of Sugammadex were also assessed (n = 18 each) in diluted Russel viper venom time (DRVVT) assays with low (DRVVT1) and high (DRVVT2) phospholipid concentrations and in a highly phospholipid-sensitive aPTT assay. Sugammadex increased PT (+9.1%; P Sugammadex dose-dependently prolonged both DRVVT1 and the highly phospholipid-sensitive aPTT assays, but additional phospholipids in the DRVVT2 assay almost abolished these prolongations. Thrombin time, a thromboelastometric thrombin generation assay, clot firmness, clot lysis, fibrinogen concentration, and activities of other coagulation factors were unaltered. Rocuronium, Sugammadex and Rocuronium combined, and saline exerted no effects. Sugammadex significantly affects various coagulation assays, but this is explainable by an apparent phospholipid-binding effect, suggesting that Sugammadex`s anticoagulant effects are likely an in vitro artifact.

New Direct Oral Anticoagulants (DOAC and Their Use Today

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Heike Schwarb

2016-03-01

Full Text Available The ideal anticoagulant is oral, has a wide therapeutic range, predictable pharmacokinetics and pharmacodynamics, a rapid onset of action, an available antidote, minimal side effects and minimal interactions with other drugs or food. With the development of the novel direct oral anticoagulants (DOAC, we now have an alternative to the traditional vitamin K antagonists (VKA for the prevention and treatment of thrombosis. DOACs have limited monitoring requirements and very predictable pharmacokinetic profiles. They were shown to be non-inferior or superior to VKA in the prophylaxis or treatment of thromboembolic events. Particularly in terms of safety they were associated with less major bleeding, including intracranial bleeding, thus providing a superior benefit for the prevention of stroke in patients with atrial fibrillation. Despite these advantages, there are remaining limitations with DOACs: their dependence on renal and hepatic function for clearance and the lack of an approved reversal agent, whereas such antidotes are successively being made available. DOACs do not need regular monitoring to assess the treatment effect but, on the other hand, they interact with other drugs and interfere with functional coagulation assays. From a practical point of view, the properties of oral administration, simple dosing without monitoring, a short half-life allowing for the possibility of uncomplicated switching or bridging, and proven safety overwhelm the disadvantages, making them an attractive option for short- or long-term anticoagulation.

Strategies to overcome or circumvent P-glycoprotein mediated multidrug resistance.

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Yuan, Hongyu; Li, Xun; Wu, Jifeng; Li, Jinpei; Qu, Xianjun; Xu, Wenfang; Tang, Wei

2008-01-01

Cancer patients who receive chemotherapy often experience intrinsic or acquired resistance to a broad spectrum of chemotherapeutic agents. The phenomenon, termed multidrug resistance (MDR), is often associated with the over-expression of P-glycoprotein, a transmembrane protein pump, which can enhance efflux of a various chemicals structurally unrelated at the expense of ATP depletion, resulting in decrease of the intracellular cytotoxic drug accumulation. The MDR has been a big threaten to the human health and the war fight for it continues. Although several other mechanisms for MDR are elucidated in recent years, considerable efforts attempting to inverse MDR are involved in exploring P-glycoprotein modulators and suppressing P-glycoprotein expression. In this review, we will report on the recent advances in various strategies for overcoming or circumventing MDR mediated by P-glycoprotein.

Aneurysmal subarachnoid hemorrhage in patients taking direct oral anticoagulants: A case series and discussion of management

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Joseph H. McMordie, MD

2018-03-01

Full Text Available Direct oral anticoagulants are becoming more commonplace for the treatment of nonvalvular atrial fibrillation and deep vein thrombosis. Unfortunately, effective reversal agents are not widely available limiting options for neurosurgical intervention during active anticoagulation. We report a case series of 3 patients treated for aneurysmal subarachnoid hemorrhage while taking direct oral anticoagulants. All three underwent open surgical clipping after adequate time was allowed for drug metabolism. Decision-making must take into account timing of intervention, drug half-life, and currently available reversal agents.

Understanding the Process of Envelope Glycoprotein Incorporation into Virions in Simian and Feline Immunodeficiency Viruses

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José L. Affranchino

2014-01-01

Full Text Available The lentiviral envelope glycoproteins (Env mediate virus entry by interacting with specific receptors present at the cell surface, thereby determining viral tropism and pathogenesis. Therefore, Env incorporation into the virions formed by assembly of the viral Gag polyprotein at the plasma membrane of the infected cells is a key step in the replication cycle of lentiviruses. Besides being useful models of human immunodeficiency virus (HIV infections in humans and valuable tools for developing AIDS therapies and vaccines, simian and feline immunodeficiency viruses (SIV and FIV, respectively are relevant animal retroviruses; the study of which provides important information on how lentiviral replication strategies have evolved. In this review, we discuss the molecular mechanisms underlying the incorporation of the SIV and FIV Env glycoproteins into viral particles.

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

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Lee T

2016-05-01

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

A novel function of N-linked glycoproteins, alpha-2-HS-glycoprotein and hemopexin: Implications for small molecule compound-mediated neuroprotection.

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Takuya Kanno

Full Text Available Therapeutic agents to the central nervous system (CNS need to be efficiently delivered to the target site of action at appropriate therapeutic levels. However, a limited number of effective drugs for the treatment of neurological diseases has been developed thus far. Further, the pharmacological mechanisms by which such therapeutic agents can protect neurons from cell death have not been fully understood. We have previously reported the novel small-molecule compound, 2-[mesityl(methylamino]-N-[4-(pyridin-2-yl-1H-imidazol-2-yl] acetamide trihydrochloride (WN1316, as a unique neuroprotectant against oxidative injury and a highly promising remedy for the treatment of amyotrophic lateral sclerosis (ALS. One of the remarkable characteristics of WN1316 is that its efficacious doses in ALS mouse models are much less than those against oxidative injury in cultured human neuronal cells. It is also noted that the WN1316 cytoprotective activity observed in cultured cells is totally dependent upon the addition of fetal bovine serum in culture medium. These findings led us to postulate some serum factors being tightly linked to the WN1316 efficacy. In this study, we sieved through fetal bovine serum proteins and identified two N-linked glycoproteins, alpha-2-HS-glycoprotein (AHSG and hemopexin (HPX, requisites to exert the WN1316 cytoprotective activity against oxidative injury in neuronal cells in vitro. Notably, the removal of glycan chains from these molecules did not affect the WN1316 cytoprotective activity. Thus, two glycoproteins, AHSG and HPX, represent a pivotal glycoprotein of the cytoprotective activity for WN1316, showing a concrete evidence for the novel glycan-independent function of serum glycoproteins in neuroprotective drug efficacy.

Anti-coagulation effect of Fc fragment against anti-β2-GP1 antibodies in mouse models with APS.

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Xie, Weidong; Zhang, Yaou; Bu, Cunya; Sun, Shijing; Hu, Shaoliang; Cai, Guoping

2011-01-01

Anti-beta (2)-glycoprotein I (anti-β2-GP1) is one of the important pathogenesis factors responsible for thrombosis formation in patients with antiphospholipid syndrome (APS). Administration of intravenous immunoglobulin (IVIg) is a common method used to inhibit the abnormal antibody levels and decrease the mortality of APS in emergency situations. We hypothesize that the Fc fragment of IgG is the molecular structure responsible for these effects. The present study investigates the beneficial effects of both recombinant and natural human Fc fragments of heterogeneous IgG against human anti-β2-GP1 antibodies in mouse models with APS. Results showed that both recombinant and natural human Fc fragments moderately but significantly decreased the levels of serum anti-β2-GP1 antibodies and had anti-coagulation effects in human β2-GP1-immunized mice. Furthermore, both recombinant and natural human Fc fragments inhibited thrombosis formation and decreased mortality in mouse models infused intravenously with human anti-β2GP1 antibodies from patients with APS. Findings suggest that the Fc fragment might be one of the active structural units of heterogeneous IgG. Thus, recombinant human Fc fragment administration may be a useful treatment for individuals with APS. Copyright © 2010 Elsevier B.V. All rights reserved.

A Functional Henipavirus Envelope Glycoprotein Pseudotyped Lentivirus Assay System

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Broder Christopher C

2010-11-01

Full Text Available Abstract Background Hendra virus (HeV and Nipah virus (NiV are newly emerged zoonotic paramyxoviruses discovered during outbreaks in Queensland, Australia in 1994 and peninsular Malaysia in 1998/9 respectively and classified within the new Henipavirus genus. Both viruses can infect a broad range of mammalian species causing severe and often-lethal disease in humans and animals, and repeated outbreaks continue to occur. Extensive laboratory studies on the host cell infection stage of HeV and NiV and the roles of their envelope glycoproteins have been hampered by their highly pathogenic nature and restriction to biosafety level-4 (BSL-4 containment. To circumvent this problem, we have developed a henipavirus envelope glycoprotein pseudotyped lentivirus assay system using either a luciferase gene or green fluorescent protein (GFP gene encoding human immunodeficiency virus type-1 (HIV-1 genome in conjunction with the HeV and NiV fusion (F and attachment (G glycoproteins. Results Functional retrovirus particles pseudotyped with henipavirus F and G glycoproteins displayed proper target cell tropism and entry and infection was dependent on the presence of the HeV and NiV receptors ephrinB2 or B3 on target cells. The functional specificity of the assay was confirmed by the lack of reporter-gene signals when particles bearing either only the F or only G glycoprotein were prepared and assayed. Virus entry could be specifically blocked when infection was carried out in the presence of a fusion inhibiting C-terminal heptad (HR-2 peptide, a well-characterized, cross-reactive, neutralizing human mAb specific for the henipavirus G glycoprotein, and soluble ephrinB2 and B3 receptors. In addition, the utility of the assay was also demonstrated by an examination of the influence of the cytoplasmic tail of F in its fusion activity and incorporation into pseudotyped virus particles by generating and testing a panel of truncation mutants of NiV and HeV F

Evaluation of computerized decision support for oral anticoagulation management based in primary care.

OpenAIRE

Fitzmaurice, D A; Hobbs, F D; Murray, E T; Bradley, C P; Holder, R

1996-01-01

BACKGROUND: Increasing indications for oral anticoagulation has led to pressure on general practices to undertake therapeutic monitoring. Computerized decision support (DSS) has been shown to be effective in hospitals for improving clinical management. Its usefulness in primary care has previously not been investigated. AIM: To test the effectiveness of using DSS for oral anticoagulation monitoring in primary care by measuring the proportions of patients adequately controlled, defined as with...

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

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

2015-01-01

Multiple factors, including proteinuria, antiphospholipid syndrome, thrombocytopenia and hypertension, are predictive of pregnancy loss in systemic lupus erythematosus (SLE). In the PROMISSE study of predictors of pregnancy loss, only a battery of lupus anticoagulant tests was predictive of a composite of adverse pregnancy outcomes. We examined the predictive value of one baseline lupus anticoagulant test (dilute Russell viper venom time) with pregnancy loss in women with SLE. From the Hopkins Lupus Cohort, there were 202 pregnancies from 175 different women after excluding twin pregnancies and pregnancies for which we did not have a first trimester assessment of lupus anticoagulant. We determined the percentage of women who had a pregnancy loss in groups defined by potential risk factors. The lupus anticoagulant was determined by dilute Russell viper venom time with appropriate mixing and confirmatory testing. Generalised estimating equations were used to calculate p values, accounting for repeated pregnancies in the same woman. The age at pregnancy was 40 (3%). 55% were Caucasian and 34% African-American. Among those with lupus anticoagulant during the first trimester, 6/16 (38%) experienced a pregnancy loss compared with only 16/186 (9%) of other pregnancies (p=0.003). In addition, those with low complement or higher disease activity had a higher rate of pregnancy loss than those without (p=0.049 and 0.005, respectively). In contrast, there was no association between elevated anticardiolipin in the first trimester and pregnancy loss. The strongest predictor of pregnancy loss in SLE in the first trimester is the lupus anticoagulant. In addition, moderate disease activity by the physician global assessment and low complement measured in the first trimester were predictive of pregnancy loss. These data suggest that treatment of the lupus anticoagulant could be considered, even in the absence of history of pregnancy loss.

The Italian START-Register on Anticoagulation with Focus on Atrial Fibrillation

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2015-01-01

START-Register – Survey on anTicoagulated pAtients RegisTer – is an independent, inception-cohort, observational, collaborative database aimed at recording prospectively the clinical history of adult patients starting anticoagulant treatment for any reason and using whatever drug. In this article we present the START-Register and give cross section baseline data focusing on non valvular atrial fibrillation (NVAF). Participants are asked to insert prospectively consecutive patients recorded as electronic file on the web-site of the registry. Required data are: demographic and clinical characteristics of patients, associated risk factors for stroke and bleeding, laboratory routine data, clinical indication for treatment, expected therapeutic range (in cases of treatment with vitamin K antagonists -VKAs). The follow-up is carried out to record: quality of treatment (for patients on VKAs), bleeding complications, thrombotic events, and the onset of any type of associated disease. To date 5252 patients have been enrolled; 97.6% were on VKAs because direct oral anticoagulants (DOAC) have been available in Italy only recently. The median age was 74 years [interquartile range (IQR) 64-80]; males 53.7%. This analysis is focused on the 3209 (61.1%) NVAF patients. Mean CHADS2 score was 2.1±1.1, CHADSVASc score was 3.1±1.3;median age was 76 years (IQR 70-81); 168 patients (5.3%) had severe renal failure [Creatinine clearance (CrCl) START-Register data shows that two-third of patients who started chronic anticoagulant treatment had NVAF, one-third of them was > 80 years with high prevalence of renal failure. PMID:26001109

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

LENUS (Irish Health Repository)

Preston, Roger J S

2012-02-01

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

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

LENUS (Irish Health Repository)

Preston, Roger J S

2009-02-27

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

Alkylation of phosphorothioated thrombin binding aptamers improves the selectivity of inhibition of tumor cell proliferation upon anticoagulation.

Science.gov (United States)

Yang, Xiantao; Zhu, Yuejie; Wang, Chao; Guan, Zhu; Zhang, Lihe; Yang, Zhenjun

2017-07-01

Recently, aptamers have been extensively researched for therapy and diagnostic applications. Thrombin-binding aptamer is a 15nt deoxyribonucleic acid screened by SELEX, it can specifically bind to thrombin and inhibit blood coagulation. Since it is also endowed with excellent antitumor activity, the intrinsic anticoagulation advantage converted to a main potential side effect for its further application in antiproliferative therapy. Site-specific alkylation was conducted through nucleophilic reaction of phosphorothioated TBAs using bromide reagents. Circular dichroism (CD) spectroscopy and surface plasmon resonance (SPR) measurements were used to evaluate anticoagulation activity, and a CCK-8 assay was used to determine cell proliferation activity. The CD spectra of the modified TBAs were weakened, and their affinity for thrombin was dramatically reduced, as reflected by the K D values. On the other hand, their inhibition of A549 cells was retained. Incorporation of different alkyls apparently disrupted the binding of TBA to thrombin while maintaining the antitumor activity. A new modification strategy was established for the use of TBA as a more selective antitumor agent. Copyright © 2017 Elsevier B.V. All rights reserved.

Generic switching of warfarin and risk of excessive anticoagulation

DEFF Research Database (Denmark)

Hellfritzsch, Maja; Rathe, Jette; Stage, Tore Bjerregaard

2016-01-01

PURPOSE: Generic switching of warfarin was recently repealed in Denmark, as adverse drug reaction (ADR) reports suggested risk of excessive anticoagulation following switches from branded to generic warfarin. We investigated this putative association in a formalized pharmacoepidemiological analysis....... METHODS: We conducted a nationwide cohort study based on Danish healthcare registries, including data from the introduction of generic warfarin until the repeal (January 2011-April 2015). We followed Danish warfarin users over time and compared the rate of incident hospitalizations due to excessive...... anticoagulation (i.e. increased INR or any bleeding requiring hospitalization) in periods following a recent switch to generic warfarin to the rate in periods without a recent switch. RESULTS: We included 105,751 warfarin users, filling a total of 1,539,640 prescriptions for warfarin (2.5% for generic warfarin...

Labelled antibody techniques in glycoprotein estimation

International Nuclear Information System (INIS)

Hazra, D.K.; Ekins, R.P.; Edwards, R.; Williams, E.S.

1977-01-01

The problems in the radioimmunoassay of the glycoprotein hormones (pituitary LH, FSH and TSH and human chlorionic gonadotrophin HGG) are reviewed viz: limited specificity and sensitivity in the clinical context, interpretation of disparity between bioassay and radioimmunoassay, and interlaboratory variability. The advantages and limitations of the labelled antibody techniques - classical immonoradiometric methods and 2-site or 125 I-anti-IgG indirect labelling modifications are reviewed in general, and their theoretical potential in glycoprotein assays examined in the light of previous work. Preliminary experiments in the development of coated tube 2-site assay for glycoproteins using 125 I anti-IgG labelling are described, including conditions for maximizing solid phase extraction of the antigen, iodination of anti-IgG, and assay conditions such as effects of temperature of incubation with antigen 'hormonefree serum', heterologous serum and detergent washing. Experiments with extraction and antigen-specific antisera raised in the same or different species are described as exemplified by LH and TSH assay systems, the latter apparently promising greater sensitivity than radioimmunoassay. Proposed experimental and mathematical optimisation and validation of the method as an assay system is outlined, and the areas for further work delineated. (orig.) [de

Adherence to oral anticoagulant therapy in secondary stroke prevention – impact of the novel oral anticoagulants

Directory of Open Access Journals (Sweden)

Luger S

2015-11-01

Full Text Available Sebastian Luger,1 Carina Hohmann,2 Daniela Niemann,1 Peter Kraft,3 Ignaz Gunreben,3 Tobias Neumann-Haefelin,2 Christoph Kleinschnitz,3 Helmuth Steinmetz,1 Christian Foerch,1 Waltraud Pfeilschifter1 1Department of Neurology, University Hospital Frankfurt, Frankfurt am Main, 2Department of Neurology, Klinikum Fulda gAG, Fulda, 3Department of Neurology, University Hospital Würzburg, Würzburg, Germany Background: Oral anticoagulant therapy (OAT potently prevents strokes in patients with atrial fibrillation. Vitamin K antagonists (VKA have been the standard of care for long-term OAT for decades, but non-VKA oral anticoagulants (NOAC have recently been approved for this indication, and raised many questions, among them their influence on medication adherence. We assessed adherence to VKA and NOAC in secondary stroke prevention. Methods: All patients treated from October 2011 to September 2012 for ischemic stroke or transient ischemic attack with a subsequent indication for OAT, at three academic hospitals were entered into a prospective registry, and baseline data and antithrombotic treatment at discharge were recorded. At the 1-year follow-up, we assessed the adherence to different OAT strategies and patients’ adherence to their respective OAT. We noted OAT changes, reasons to change treatment, and factors that influence persistence to the prescribed OAT. Results: In patients discharged on OAT, we achieved a fatality corrected response rate of 73.3% (n=209. A total of 92% of these patients received OAT at the 1-year follow-up. We observed good adherence to both VKA and NOAC (VKA, 80.9%; NOAC, 74.8%; P=0.243 with a statistically nonsignificant tendency toward a weaker adherence to dabigatran. Disability at 1-year follow-up was an independent predictor of lower adherence to any OAT after multivariate analysis, whereas the choice of OAT did not have a relevant influence. Conclusion: One-year adherence to OAT after stroke is strong (>90% and patients

Comparing new anticoagulants.

Science.gov (United States)

Wooten, James M

2012-12-01

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

Individual contributions of the human metapneumovirus F, G, and SH surface glycoproteins to the induction of neutralizing antibodies and protective immunity

International Nuclear Information System (INIS)

Skiadopoulos, Mario H.; Biacchesi, Stephane; Buchholz, Ursula J.; Amaro-Carambot, Emerito; Surman, Sonja R.; Collins, Peter L.; Murphy, Brian R.

2006-01-01

We evaluated the individual contributions of the three surface glycoproteins of human metapneumovirus (HMPV), namely the fusion F, attachment G, and small hydrophobic SH proteins, to the induction of serum HMPV-binding antibodies, serum HMPV-neutralizing antibodies, and protective immunity. Using reverse genetics, each HMPV protein was expressed individually from an added gene in recombinant human parainfluenza virus type 1 (rHPIV1) and used to infect hamsters once or twice by the intranasal route. The F protein was highly immunogenic and protective, whereas G and SH were only weakly or negligibly immunogenic and protective, respectively. Thus, in contrast to other paramyxoviruses, the HMPV attachment G protein is not a major neutralization or protective antigen. Also, although the SH protein of HMPV is a virion protein that is much larger than its counterparts in previously studied paramyxoviruses, it does not appear to be a significant neutralization or protective antigen

Atrial fibrillation and stroke prevention practices in patients with candidacy for anticoagulation therapy

International Nuclear Information System (INIS)

Ullah, I.; Ahmad, S.; Hayat, Y.

2015-01-01

Background: Stroke secondary to Atrial Fibrillation is usually due to thrombi formed in the left atrium and left atrial appendage embolizing to cause ischemic stroke. Therefore, in patients with Atrial Fibrillation, antithrombotic therapy is recommended to prevent stroke. Vitamin K antagonist therapy is most widely used antithrombotic therapy for patients with valvular and non valvular AF. Aspirin is recommended only in low risk patients. This study was conducted to determine the stroke prevention practices in local patients with atrial fibrillation who were candidates for anticoagulation therapy. Method: This was descriptive cross sectional study conducted at Cardiovascular Department Lady Reading Hospital Peshawar and Cardiology Department Hayatabad Medical Complex Peshawar. Sampling technique was non probability consecutive. Patients visiting OPD of respective hospitals with EKG evidence of AF and having CHADES VASC score 2 or more or having mitral stenosis and AF were included in the study. Patients with additional indications for anticoagulation were excluded from the study. Results: A total of 205 patients with atrial fibrillation were studied. Mean age was 60.7±14.7 years. Male were 55.6 percentage (n=114) while 44.4 percentage (n=91) were female. Of these 149 (72.7 percentage) were candidates for anticoagulation based on CHA2DS2 VASc score of 2 and more or mitral stenosis with AF. Only 27.5 percentage (n=41) patients were adequately treated with anticoagulant therapy using VKA or novel oral anticoagulant drugs. Majority of them were getting dual antiplatelet therapy (DAPT). Conclusion: Most patients with AF and high risk characteristics for thromboembolism are not receiving proper stroke prevention therapies. (author)

Does small mammal prey guild affect the exposure of predators to anticoagulant rodenticides?

International Nuclear Information System (INIS)

Tosh, D.G.; McDonald, R.A.; Bearhop, S.; Lllewellyn, N.R.; Fee, S.; Sharp, E.A.; Barnett, E.A.; Shore, R.F.

2011-01-01

Ireland has a restricted small mammal prey guild but still includes species most likely to consume anticoagulant rodenticide (AR) baits. This may enhance secondary exposure of predators to ARs. We compared liver AR residues in foxes (Vulpes vulpes) in Northern Ireland (NI) with those in foxes from Great Britain which has a more diverse prey guild but similar agricultural use of ARs. Liver ARs were detected in 84% of NI foxes, more than in a comparable sample of foxes from Scotland and similar to that of suspected AR poisoned animals from England and Wales. High exposure in NI foxes is probably due to greater predation of commensal rodents and non-target species most likely to take AR baits, and may also partly reflect greater exposure to highly persistent brodifacoum and flocoumafen. High exposure is likely to enhance risk and Ireland may be a sentinel for potential effects on predator populations. - Highlights: → Exposure of a predator to anticoagulant rodenticides was compared in Britain and Ireland. → Exposure was higher in Ireland. → Differences driven by small mammal prey guilds. → Ireland a potential sentinel for predator exposure to anticoagulants. - Restriction of the small mammal prey guild is associated with enhanced exposure of predators to anticoagulant rodenticides.

A sheep hydatid cyst glycoprotein as receptors for three toxic lectins, as well as Abrus precatorius and Ricinus communis agglutinins.

Science.gov (United States)

Wu, A M; Song, S C; Wu, J H; Pfüller, U; Chow, L P; Lin, J Y

1995-01-18

The binding properties of a glycoprotein with blood group P1 specificity isolated from sheep hydatid cyst fluid with Gal and GalNAc specific lectins was investigated by quantitative precipitin and precipitin inhibition assays. The glycoprotein completely precipitated Ricinus communis agglutinin (RCA1), Abrus precatorius agglutinin (APA) and Mistletoe toxic lectin-I (ML-I). Only 1.0 microgram of P1 glycoprotein was required to precipitate 50% of 5.1 micrograms ML-I nitrogen. It also reacted well with abrin-a and ricin, precipitating over 73% of the lectin nitrogen added, but poorly or weakly with Dolichos biflorus (DBL), Vicia villosa (VVL, a mixture of A4, A2B2 and B4), VVL-B4, Arachis hypogaea (PNA), Maclura pomifera (MPL), Bauchinia purpurea alba (BPL) and Wistaria floribunda (WFL) lectins. When an inhibition assay in the range of 5.1 micrograms N to 5.9 micrograms N of lectins (ML-I, abrin-a; ricin, RCA1, and APA, and 10 micrograms P1 active glycoprotein interaction was performed; from 76 to 100% of the precipitations were inhibited by 0.44 and 0.52 mumol of Gal alpha 1-->4Gal and Gal beta 1-->4GlcNAc, respectively, but not or insignificantly with 1.72 mumol of GlcNAc. The Gal alpha 1-->4Gal disaccharide found in this P1 active glycoprotein is a frequently occurring sequence of many glycosphingolipids located at the surface of mammalian cell membranes, especially human erythrocytes and intestinal cells for ligand binding and microbial toxin attachment. The present finding suggests that the Gal alpha 1-->4Gal beta 1-->4GlcNAc sequence in this P1 active glycoprotein is one of the best glycoprotein receptors for three toxic lectins (ricin, abrin-a, and ML-I) as well as for APA, and RCA1, and the result of inhibition assay implies that these lectins are recognizing part or all of the Gal alpha 1-->4Gal beta 1-->4GlcNAc sequence in the P1 active glycoprotein.

Practical considerations in emergency management of bleeding in the setting of target-specific oral anticoagulants.

Science.gov (United States)

Miller, Michael P; Trujillo, Toby C; Nordenholz, Kristen E

2014-04-01

The recent arrival of the target-specific oral anticoagulants (TSOACs) offers potential advantages in the field of anticoagulation. However, there are no rapid and accurate and routinely available laboratory assays to evaluate their contribution to clinical bleeding. With the expanding clinical indications for the TSOACs, and the arrival of newer reversal agents on the market, the emergency clinician will need to be familiar with drug specifics as well as methods for anticoagulation reversal. This review offers a summary of the literature and some practical strategies for the approach to the patient taking TSOACs and the management of bleeding in these cases. Copyright © 2014 Elsevier Inc. All rights reserved.

Adipokine zinc-α2-glycoprotein regulated by growth hormone and linked to insulin sensitivity.

Science.gov (United States)

Balaz, Miroslav; Ukropcova, Barbara; Kurdiova, Timea; Gajdosechova, Lucia; Vlcek, Miroslav; Janakova, Zuzana; Fedeles, Jozef; Pura, Mikulas; Gasperikova, Daniela; Smith, Steven R; Tkacova, Ruzena; Klimes, Iwar; Payer, Juraj; Wolfrum, Christian; Ukropec, Jozef

2015-02-01

Hypertrophic obesity is associated with impaired insulin sensitivity and lipid-mobilizing activity of zinc-α2-glycoprotein. Adipose tissue (AT) of growth hormone (GH) -deficient patients is characterized by extreme adipocyte hypertrophy due to defects in AT lipid metabolism. It was hypothesized that zinc-α2-glycoprotein is regulated by GH and mediates some of its beneficial effects in AT. AT from patients with GH deficiency and individuals with obesity-related GH deficit was obtained before and after 5-year and 24-month GH supplementation therapy. GH action was tested in primary human adipocytes. Relationships of GH and zinc-α2-glycoprotein with adipocyte size and insulin sensitivity were evaluated in nondiabetic patients with noncancerous cachexia and hypertrophic obesity. AT in GH-deficient adults displayed a substantial reduction of zinc-α2-glycoprotein. GH therapy normalized AT zinc-α2-glycoprotein. Obesity-related relative GH deficit was associated with almost 80% reduction of zinc-α2-glycoprotein mRNA in AT. GH increased zinc-α2-glycoprotein mRNA in both AT of obese men and primary human adipocytes. Interdependence of GH and zinc-α2-glycoprotein in regulating AT morphology and metabolic phenotype was evident from their relationship with adipocyte size and AT-specific and whole-body insulin sensitivity. The results demonstrate that GH is involved in regulation of AT zinc-α2-glycoprotein; however, the molecular mechanism linking GH and zinc-α2-glycoprotein in AT is yet unknown. © 2014 The Obesity Society.

Gaps in monitoring during oral anticoagulation: insights into care transitions, monitoring barriers, and medication nonadherence.

Science.gov (United States)

Rose, Adam J; Miller, Donald R; Ozonoff, Al; Berlowitz, Dan R; Ash, Arlene S; Zhao, Shibei; Reisman, Joel I; Hylek, Elaine M

2013-03-01

Among patients receiving oral anticoagulation, a gap of > 56 days between international normalized ratio tests suggests loss to follow-up that could lead to poor anticoagulation control and serious adverse events. We studied long-term oral anticoagulation care for 56,490 patients aged 65 years and older at 100 sites of care in the Veterans Health Administration. We used the rate of gaps in monitoring per patient-year to predict percentage time in therapeutic range (TTR) at the 100 sites. Many patients (45%) had at least one gap in monitoring during an average of 1.6 years of observation; 5% had two or more gaps per year. The median gap duration was 74 days (interquartile range, 62-107). The average TTR for patients with two or more gaps per year was 10 percentage points lower than for patients without gaps (P < .001). Patient-level predictors of gaps included nonwhite race, area poverty, greater distance from care, dementia, and major depression. Site-level gaps per patient-year varied from 0.19 to 1.78; each one-unit increase was associated with a 9.2 percentage point decrease in site-level TTR (P < .001). Site-level gap rates varied widely within an integrated care system. Sites with more gaps per patient-year had worse anticoagulation control. Strategies to address and reduce gaps in monitoring may improve anticoagulation control.

Risk scores and geriatric profile: can they really help us in anticoagulation decision making among older patients suffering from atrial fibrillation?

Science.gov (United States)

Maes, Frédéric; Dalleur, Olivia; Henrard, Séverine; Wouters, Dominique; Scavée, Christophe; Spinewine, Anne; Boland, Benoit

2014-01-01

Anticoagulation for the prevention of cardio-embolism is most frequently indicated but largely underused in frail older patients with atrial fibrillation (AF). This study aimed at identifying characteristics associated with anticoagulation underuse. A cross-sectional study of consecutive geriatric patients aged ≥75 years, with AF and clear anticoagulation indication (CHADS₂ [Congestive heart failure, Hypertension, Age >75, Diabetes mellitus, and prior Stroke or transient ischemic attack] ≥2) upon hospital admission. All patients benefited from a comprehensive geriatric assessment. Their risks of stroke and bleeding were predicted using CHADS₂ and HEMORR2HAGES (Hepatic or renal disease, Ethanol abuse, Malignancy, Older (age >75 years), Reduced platelet count or function, Rebleed risk, Hypertension (uncontrolled), Anemia, Genetic factors, Excessive fall risk, and Stroke) scores, respectively. Anticoagulation underuse was observed in 384 (50%) of 773 geriatric patients with AF (median age 85 years; female 57%, cognitive disorder 33%, nursing home 20%). No geriatric characteristic was found to be associated with anticoagulation underuse. Conversely, anticoagulation underuse was markedly increased in the patients treated with aspirin (odds ratio [OR] [95% confidence interval]: 5.3 [3.8; 7.5]). Other independent predictors of anticoagulation underuse were ethanol abuse (OR: 4.0 [1.4; 13.3]) and age ≥90 years (OR: 2.0 [1.2; 3.4]). Anticoagulation underuse was not inferior in patients with a lower bleeding risk and/or a higher stroke risk and underuse was surprisingly not inferior either in the AF patients who had previously had a stroke. Half of this geriatric population did not receive any anticoagulation despite a clear indication, regardless of their individual bleeding or stroke risks. Aspirin use is the main characteristic associated with anticoagulation underuse.

Best strategies for patient education about anticoagulation with warfarin: a systematic review

Directory of Open Access Journals (Sweden)

Singh Sonal

2008-02-01

Full Text Available Abstract Background Patient education is an essential component in quality management of the anticoagulated patient. Because it is time consuming for clinicians and overwhelming for patients, education of the anticoagulated patient is often neglected. We surveyed the medical literature in order to identify the best patient education strategies. Methods Study Selection: Two reviewers independently searched the MEDLINE and Google Scholar databases (last search March 2007 using the terms "warfarin" or "anticoagulation", and "patient education". The initial search identified 206 citations, A total of 166 citations were excluded because patients were of pediatric age (4, the article was not related to patient education (48, did not contain original data or inadequate program description (141, was focused solely on patient self-testing (1, was a duplicate citation (3, the article was judged otherwise irrelevant (44, or no abstract was available (25. Data Extraction: Clinical setting, study design, group size, content source, time and personnel involved, educational strategy and domains, measures of knowledge retention. Results Data Synthesis: A total of 32 articles were ultimately used for data extraction. Thirteen articles adequately described features of the educational strategy. Five programs used a nurse or pharmacist, 4 used a physician, and 2 studies used other personnel/vehicles (lay educators (1, videotapes (1. The duration of the educational intervention ranged from 1 to 10 sessions. Patient group size most often averaged 3 to 5 patients but ranged from as low as 1 patient to as much as 11 patients. Although 12 articles offered information about education content, the wording and lack of detail in the description made it too difficult to accurately assign categories of education topics and to compare articles with one another. For the 17 articles that reported measures of patient knowledge, 5 of the 17 sites where the surveys were

Cell Surface Glycoprotein of Reactive Stromal Fibroblasts as a Potential Antibody Target in Human Epithelial Cancers

Science.gov (United States)

Garin-Chesa, Pilar; Old, Lloyd J.; Rettig, Wolfgang J.

1990-09-01

The F19 antigen is a cell surface glycoprotein (M_r, 95,000) of human sarcomas and proliferating, cultured fibroblasts that is absent from resting fibroblasts in normal adult tissues. Normal and malignant epithelial cells are also F19^-. The present immunohistochemical study describes induction of F19 in the reactive mesenchyme of epithelial tumors. F19^+ fibroblasts were found in primary and metastatic carcinomas, including colorectal (18 of 18 cases studied), breast (14/14), ovarian (21/21), bladder (9/10), and lung carcinomas (13/13). In contrast, the stroma of benign colorectal adenomas, fibrocystic disease and fibroadenomas of breast, benign prostate hyperplasia, in situ bladder carcinomas, and benign ovarian tumors showed no or only moderate numbers of F19^+ fibroblasts. Analysis of dermal incision wounds revealed that F19 is strongly induced during scar formation. Comparison of F19 with the extracellular matrix protein tenascin, a putative marker of tumor mesenchyme, showed a cellular staining pattern for F19 vs. the extracellular matrix pattern for tenascin and widespread expression of tenascin in F19^- normal tissues and benign tumors. Our results suggest that the F19^+ phenotype correlates with specialized fibroblast functions in wound healing and malignant tumor growth. Because of its abundance in tumor mesenchyme, F19 may serve as a target for antibodies labeled with radioisotopes or toxic agents, or inflammatogenic antibodies, in carcinoma patients.

Scoring and psychometric validation of the Perception of Anticoagulant Treatment Questionnaire (PACT-Q©

Directory of Open Access Journals (Sweden)

Essers B

2009-04-01

Full Text Available Abstract Background The 'Perception of Anti-Coagulant Treatment Questionnaire' (PACT-Q was developed to assess patients' expectations of, and satisfaction with their anticoagulant treatment. This questionnaire needs to be finalised and psychometrically validated. Methods The PACT-Q was included in the United States, the Netherlands and France into three phase III multinational clinical trials conducted to evaluate efficacy and safety of a new long-acting anticoagulant drug (idraparinux compared to vitamin K antagonist (VKA. PACT-Q was administered to patients with deep venous thrombosis (DVT, atrial fibrillation (AF or pulmonary embolism (PE at Day 1, to assess patients' expectations, and at 3 and 6 months to assess patients' satisfaction and treatment convenience and burden. The final structure of the PACT-Q (Principal Component Analysis – PCA – with Varimax Rotation was first determined and its psychometric properties were then measured with validity of the structure (Multitrait analysis, internal consistency reliability (Cronbach's alpha coefficients and known-group validity. Results PCA and multitrait analyses showed the multidimensionality of the "Treatment Expectations" dimension, comprising 7 items that had to be scored independently. The "Convenience" and "Burden of Disease and Treatment" dimensions of the hypothesised original structure of the questionnaire were combined, thus resulting in 13 items grouped into the single dimension "Convenience". The "Anticoagulant Treatment Satisfaction" dimension remained unchanged and included 7 items. All items of the "Convenience" and "Anticoagulant Treatment Satisfaction" dimensions displayed good convergent and discriminant validity. The internal consistency reliability was good, with a Cronbach's alpha of 0.84 for the "Convenience" dimension, and 0.76 for the "Anticoagulant Treatment Satisfaction" dimension. Known-group validity was good, especially with regard to occurrence of

Characterization and structural analysis of a potent anticoagulant phospholipase A2 from Pseudechis australis snake venom.

Science.gov (United States)

Du, Qianyun Sharon; Trabi, Manuela; Richards, Renée Stirling; Mirtschin, Peter; Madaras, Frank; Nouwens, Amanda; Zhao, Kong-Nan; de Jersey, John; Lavin, Martin F; Guddat, Luke W; Masci, Paul P

2016-03-01

Pseudechis australis is one of the most venomous and lethal snakes in Australia. Numerous phospholipase A2 (PLA2) isoforms constitute a major portion of its venom, some of which have previously been shown to exhibit not only enzymatic, but also haemolytic, neurotoxic and anticoagulant activities. Here, we have purified a potent anticoagulant PLA2 (identified as PA11) from P. australis venom to investigate its phospholipase, anticoagulant, haemolytic and cytotoxic activities and shown that addition of 11 nM PA11 resulted in a doubling of the clotting time of recalcified whole blood. We have also demonstrated that PA11 has high PLA2 enzymatic activity (10.9 × 10(4) Units/mg), but low haemolytic activity (0.6% of red blood cells hydrolysed in the presence of 1 nM PA11). PA11 at a concentration lower than 600 nM is not cytotoxic towards human cultured cells. Chemical modification experiments using p-bromophenacyl bromide have provided evidence that the catalytic histidine of PA11 is critical for the anticoagulant activity of this PLA2. PA11 that was subjected to trypsin digestion without previous reduction and alkylation of the disulfide bonds maintained enzymatic and anticoagulant activity, suggesting that proteolysis alone cannot abolish these properties. Consistent with these results, administration of PA11 by gavage in a rabbit stasis thrombosis model increased the clotting time of recalcified citrated whole blood by a factor of four. These data suggest that PA11 has potential to be developed as an anticoagulant in a clinical setting. Copyright © 2015. Published by Elsevier Ltd.

Major surface glycoproteins of insect forms of Trypanosoma brucei are not essential for cyclical transmission by tsetse.

Directory of Open Access Journals (Sweden)

Erik Vassella

Full Text Available Procyclic forms of Trypanosoma brucei reside in the midgut of tsetse flies where they are covered by several million copies of glycosylphosphatidylinositol-anchored proteins known as procyclins. It has been proposed that procyclins protect parasites against proteases and/or participate in tropism, directing them from the midgut to the salivary glands. There are four different procyclin genes, each subject to elaborate levels of regulation. To determine if procyclins are essential for survival and transmission of T. brucei, all four genes were deleted and parasite fitness was compared in vitro and in vivo. When co-cultured in vitro, the null mutant and wild type trypanosomes (tagged with cyan fluorescent protein maintained a near-constant equilibrium. In contrast, when flies were infected with the same mixture, the null mutant was rapidly overgrown in the midgut, reflecting a reduction in fitness in vivo. Although the null mutant is patently defective in competition with procyclin-positive parasites, on its own it can complete the life cycle and generate infectious metacyclic forms. The procyclic form of T. brucei thus differs strikingly from the bloodstream form, which does not tolerate any perturbation of its variant surface glycoprotein coat, and from other parasites such as Plasmodium berghei, which requires the circumsporozoite protein for successful transmission to a new host.

Using Artificial Intelligence to Reduce the Risk of Nonadherence in Patients on Anticoagulation Therapy.

Science.gov (United States)

Labovitz, Daniel L; Shafner, Laura; Reyes Gil, Morayma; Virmani, Deepti; Hanina, Adam

2017-05-01

This study evaluated the use of an artificial intelligence platform on mobile devices in measuring and increasing medication adherence in stroke patients on anticoagulation therapy. The introduction of direct oral anticoagulants, while reducing the need for monitoring, have also placed pressure on patients to self-manage. Suboptimal adherence goes undetected as routine laboratory tests are not reliable indicators of adherence, placing patients at increased risk of stroke and bleeding. A randomized, parallel-group, 12-week study was conducted in adults (n=28) with recently diagnosed ischemic stroke receiving any anticoagulation. Patients were randomized to daily monitoring by the artificial intelligence platform (intervention) or to no daily monitoring (control). The artificial intelligence application visually identified the patient, the medication, and the confirmed ingestion. Adherence was measured by pill counts and plasma sampling in both groups. For all patients (n=28), mean (SD) age was 57 years (13.2 years) and 53.6% were women. Mean (SD) cumulative adherence based on the artificial intelligence platform was 90.5% (7.5%). Plasma drug concentration levels indicated that adherence was 100% (15 of 15) and 50% (6 of 12) in the intervention and control groups, respectively. Patients, some with little experience using a smartphone, successfully used the technology and demonstrated a 50% improvement in adherence based on plasma drug concentration levels. For patients receiving direct oral anticoagulants, absolute improvement increased to 67%. Real-time monitoring has the potential to increase adherence and change behavior, particularly in patients on direct oral anticoagulant therapy. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02599259. © 2017 American Heart Association, Inc.

Safety and efficacy of anticoagulation for secondary stroke prevention in atrial fibrillation patients: The AMADEUS trial

NARCIS (Netherlands)

Lane, D.A.; Kamphuisen, P.W.; Minini, P.; Buller, H.R.; Lip, G.Y.H.

2010-01-01

ackground: Patients with atrial fibrillation (AF) and previous ischemic stroke are at high risk of recurrent stroke, but are also perceived to be at increased bleeding risk while treated with anticoagulants. Methods: Post-hoc analyses examined the efficacy and safety of anticoagulation of 4576 AF

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

DEFF Research Database (Denmark)

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

2009-01-01

OBJECTIVES: To study the impact of anticoagulation on major cerebral events in patients with left-sided Staphylococcus aureus infective endocarditis (IE). METHODS: A prospective cohort study; the use of anticoagulation and the relation to major cerebral events was evaluated separately at onset...... of admission and during hospitalization. RESULTS: Overall, 70 out of 175 patients (40%; 95% CI: 33-47%) experienced major cerebral events during the course of the disease, cerebral ischaemic stroke occured in 59 patients (34%; 95% CI: 27-41%), cerebral infection in 23 patients (14%; 95% CI: 9...

The first pharmacist-managed anticoagulation clinic under a collaborative practice agreement in Qatar: clinical and patient-oriented outcomes.

Science.gov (United States)

Elewa, H F; AbdelSamad, O; Elmubark, A E; Al-Taweel, H M; Mohamed, A; Kheir, N; Mohamed Ibrahim, M I; Awaisu, A

2016-08-01

Optimal outpatient anticoagulation management requires a systematic and coordinated approach. Extensive evidence regarding the benefits of pharmacist-managed anticoagulation services has been reported in the literature. The quality and outcomes associated with pharmacist-managed anticoagulation clinics under collaborative practice agreements in the Middle East have rarely been reported. The first pharmacist-managed ambulatory anticoagulation clinic in Qatar was launched at Al-Wakrah Hospital in March 2013. The objectives of this study were to: (i) describe the practice model of the clinic, (ii) evaluate the quality of the clinic [i.e. the time in therapeutic range (TTR)] and the clinical outcomes (i.e. the efficacy and safety), and (iii) determine the patients' satisfaction and overall quality of life (QoL). Clinical outcome data were collected through a retrospective chart review of all patients managed from March 2013 to October 2014 at the pharmacist-managed anticoagulation clinic. Furthermore, the patient-oriented outcomes data were prospectively collected using the 24-item Duke Anticoagulation Satisfaction Scale (DASS). Each item was assessed using a 7-point Likert-type scale on which lower scores indicated better QoL and greater satisfaction. The clinical outcome data analyses included 119 patients who were enrolled at the clinic during the 19-month study period. The mean number of international normalized ratio (INR) tests/month was 65 ± 9, the average testing frequency was 2·7 ± 1·6 weeks, and the average %TTR was 76·8 ± 22·9%. There was one major bleeding event (0·67%/year), 12 minor bleeding events (8%/year) and two thromboembolic events (1·35%/year) recorded during the study period. Of the 119 patients, 50 participated in the satisfaction and QoL survey. The median (IQR) total QoL score of these subjects was 63 (48) (minimum-maximum achievable score: 24-168). Seventy-six per cent of the patients indicated 'a lot to very much' in terms of their

Histochemical and structural analysis of mucous glycoprotein secreted by the gill of Mytilus edulis

International Nuclear Information System (INIS)

Ahn, Hae-Young.

1988-01-01

Studies were carried out to characterized various mucous cells in the gill filament, to ascertain structural characteristics of the secreted mucous glycoproteins, and to determine the ability of the gill epithelium to incorporate [ 14 C]glucosamine as a precursor in the biosynthesis and secretion of mucous glycoproteins. Using histochemical staining techniques, mucous cells containing neutral and acidic mucins were found in the lateral region, whereas mucous cells containing primarily neutral or sulfated mucins were found in the postlateral region. Serotonin, but not dopamine, stimulated the mucous secretion. In tissues pretreated with [ 14 C]glucosamine, the secreted glycoproteins contain incorporated radiolabel. Analysis by column chromatography using Bio-Gel P-2 and P-6 shows that the secretion contains two glycoprotein populations. Glycoprotein II has a molecular weight of 2.3 x 10 4 daltons. Upon alkaline reductive borohydride cleavage of the O-glycosidic linkages of glycoprotein I, about 70% of the radiolabel was removed from the protein. Gas chromatographic analysis of the carbohydrate composition shows that the glycoproteins contains N-acetylglucosamine (GluNAc), N-acetylgalactosamine (GalNAc), and galactose, fucose and mannose. Amino acid analysis shows that the glycoproteins are rich in serine, threonine and proline

The risk of venous thromboembolism with aspirin compared to anticoagulants after hip and knee arthroplasty.

Science.gov (United States)

Chu, Janet N; Maselli, Judith; Auerbach, Andrew D; Fang, Margaret C

2017-07-01

Recent guidelines include aspirin as an option to prevent venous thromboembolism (VTE) in selected patients undergoing hip or knee replacement surgery. However, the efficacy of aspirin after arthroplasty has not been well-defined, particularly in more contemporary patient populations. We compared rates of post-operative VTE between patients who received aspirin-only versus anticoagulants after hip or knee arthroplasty, using data from a large US-based administrative database. We conducted a retrospective cohort study of 231,780 adults who underwent total knee arthroplasty and 110,621 who underwent total hip arthroplasty in 2009-2012 and who received pharmacologic VTE prophylaxis (aspirin or anticoagulant) within the first 7days after surgery. We compared the risk of post-operative VTE between patients receiving aspirin-only vs. anticoagulants, controlling for clinical and hospital characteristics using multivariable logistic regression with propensity score adjustment. Aspirin-only prophylaxis was administered to 7.5% of patients after knee arthroplasty and 8.0% after hip arthroplasty. Post-operative VTE was diagnosed in 2217 (0.96%) patients after knee arthroplasty and 454 (0.41%) after hip arthroplasty. Compared to anticoagulants, aspirin was not associated with a higher risk for post-operative VTE either after knee arthroplasty (adjusted odds ratio and 95% confidence interval [OR] 0.34 [0.24-0.48]) or hip arthroplasty (OR 0.82 [0.45-1.51]). Aspirin was uncommonly administered as the sole prophylactic agent after hip or knee arthroplasty in this study. However, patients who received aspirin-only had similar rates of post-operative VTE compared to patients who received anticoagulants. Further research should focus on distinguishing which patients benefit more from anticoagulants versus aspirin after arthroplasty. Copyright © 2017 Elsevier Ltd. All rights reserved.

Distinctive receptor binding properties of the surface glycoprotein of a natural Feline Leukemia Virus isolate with unusual disease spectrum

Directory of Open Access Journals (Sweden)

Albritton Lorraine M

2011-05-01

Full Text Available Abstract Background Feline leukemia virus (FeLV-945, a member of the FeLV-A subgroup, was previously isolated from a cohort of naturally infected cats. An unusual multicentric lymphoma of non-T-cell origin was observed in natural and experimental infection with FeLV-945. Previous studies implicated the FeLV-945 surface glycoprotein (SU as a determinant of disease outcome by an as yet unknown mechanism. The present studies demonstrate that FeLV-945 SU confers distinctive properties of binding to the cell surface receptor. Results Virions bearing the FeLV-945 Env protein were observed to bind the cell surface receptor with significantly increased efficiency, as was soluble FeLV-945 SU protein, as compared to the corresponding virions or soluble protein from a prototype FeLV-A isolate. SU proteins cloned from other cohort isolates exhibited increased binding efficiency comparable to or greater than FeLV-945 SU. Mutational analysis implicated a domain containing variable region B (VRB to be the major determinant of increased receptor binding, and identified a single residue, valine 186, to be responsible for the effect. Conclusions The FeLV-945 SU protein binds its cell surface receptor, feTHTR1, with significantly greater efficiency than does that of prototype FeLV-A (FeLV-A/61E when present on the surface of virus particles or in soluble form, demonstrating a 2-fold difference in the relative dissociation constant. The results implicate a single residue, valine 186, as the major determinant of increased binding affinity. Computational modeling suggests a molecular mechanism by which residue 186 interacts with the receptor-binding domain through residue glutamine 110 to effect increased binding affinity. Through its increased receptor binding affinity, FeLV-945 SU might function in pathogenesis by increasing the rate of virus entry and spread in vivo, or by facilitating entry into a novel target cell with a low receptor density.

Monoclonal antibody to an external epitope of the human mdr1 P-glycoprotein

NARCIS (Netherlands)

Arceci, R. J.; Stieglitz, K.; Bras, J.; Schinkel, A.; Baas, F.; Croop, J.

1993-01-01

A membrane glycoprotein, termed P-glycoprotein, has been shown to be responsible for cross-resistance to a broad range of structurally and functionally distinct cytotoxic agents. P-glycoprotein, encoded in humans by the mdr1 gene, functions as an energy-dependent efflux pump to exclude these

Characterization of swiftlet edible bird nest, a mucin glycoprotein, and its adulterants by Raman microspectroscopy.

Science.gov (United States)

Shim, Eric K S; Chandra, Gleen F; Pedireddy, S; Lee, Soo-Y

2016-09-01

Edible bird's nest (EBN) is made from the glutinous salivary secretion of highly concentrated mucin glycoprotein by swiftlets (genus Aerodramus or Collocalia ) native to the Indo-Pacific region. The unique Raman spectrum of EBN has vibrational lines that can be assigned to peptides and saccharides in the glycoprotein, and it can be used to screen for adulteration. The common edible adulterants classified into two types. Type I adulterants, such as fish bladder, pork skin, karaya gum, coralline seaweed, agar strips, and tremella fungus, were solids which adhered externally on the surface of the EBN cement. They can usually be detected with a microscope based on differences in the surface structure. Type II adulterants were water soluble substances such as saccharides (e.g., glucose, sucrose), polypeptides (e.g., hydrolyzed collagen) and salts (e.g. monosodium glutamate) which can be readily soaked up by the EBN hydrogel when moist and adsorbed internally in the EBN cement matrix forming a composite upon drying, making them difficult to detect visually. The present study showed that Raman microspectroscopy offers a rapid, non-invasive, and label free technique to detect both Type I and II adulterants in EBN.

Fatal rebleeding following coil embolization of cerebral aneurysms: the role of long-term systemic anticoagulation

International Nuclear Information System (INIS)

Sinson, G.; Bagley, L.J.; Hurst, R.W.; Flamm, E.S.

2001-01-01

Embolization of cerebral aneurysms has become a common technique. Its impact on subsequent medical management of the patient is not well known. We report two patients who presented in a poor neurological grade after subarachnoid hemorrhage from posterior communicating artery aneurysms. Both were treated by coil embolization and both developed subclavian vein thrombosis, requiring systemic anticoagulation, initiated 11 and 21 days after embolization, respectively. Both developed a large, fatal intracranial hemorrhage adjacent to the embolized aneurysm in the fourth week of anticoagulation. Systemic anticoagulation of patients who have had a ruptured aneurysm treated by coil embolization may carry a significant risk of rebleeding. Alternate management strategies should be considered in these patients. (orig.)

Fatal rebleeding following coil embolization of cerebral aneurysms: the role of long-term systemic anticoagulation

Energy Technology Data Exchange (ETDEWEB)

Sinson, G. [Dept. of Neurosurgery, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Bagley, L.J.; Hurst, R.W. [Dept. of Radiology-Neuroradiology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Flamm, E.S. [Hyman-Newman Institute for Neurology and Neurosurgery, New York, NY (United States)

2001-05-01

Embolization of cerebral aneurysms has become a common technique. Its impact on subsequent medical management of the patient is not well known. We report two patients who presented in a poor neurological grade after subarachnoid hemorrhage from posterior communicating artery aneurysms. Both were treated by coil embolization and both developed subclavian vein thrombosis, requiring systemic anticoagulation, initiated 11 and 21 days after embolization, respectively. Both developed a large, fatal intracranial hemorrhage adjacent to the embolized aneurysm in the fourth week of anticoagulation. Systemic anticoagulation of patients who have had a ruptured aneurysm treated by coil embolization may carry a significant risk of rebleeding. Alternate management strategies should be considered in these patients. (orig.)

Intermittent vs. Continuous Anticoagulation theRapy in patiEnts with Atrial Fibrillation (iCARE-AF): a randomized pilot study.

Science.gov (United States)

Stavrakis, Stavros; Stoner, Julie A; Kardokus, Joel; Garabelli, Paul J; Po, Sunny S; Lazzara, Ralph

2017-01-01

We hypothesized that intermittent anticoagulation based on daily rhythm monitoring using the novel oral anticoagulants (NOACs) is feasible and safe among patients with paroxysmal atrial fibrillation (AF). Patients with paroxysmal AF and ≥1 risk factors for stroke were randomized to either intermittent or continuous anticoagulation. Those in the intermittent group were instructed to transmit a daily ECG using an iPhone-based rhythm monitoring device. If AF was detected, patients received one of the NOACs for 48 h-1 week. Patients who failed to transmit an ECG for three consecutive days or more than 7 days total were crossed over to continuous anticoagulation. Patients in the continuous group received one of the NOACs. Fifty-eight patients were randomized to either intermittent (n = 29) or continuous anticoagulation (n = 29). Over a median follow-up of 20 months, 20 patients in the intermittent group failed to submit a daily ECG at least once (median three failed submissions). Four patients (14 %) crossed over to continuous anticoagulation due to failure to submit an ECG for three consecutive days. One stroke (continuous group) occurred during the study. Major bleeding occurred in two patients in the continuous and one patient in the intermittent group, after crossing over to continuous anticoagulation. In a prespecified per-protocol analysis, gastrointestinal bleeding was more frequent in the continuous group (16 vs. 0 %; p = 0.047). Intermittent anticoagulation based on daily rhythm monitoring is feasible and may decrease bleeding in low-risk patients with paroxysmal AF. A larger trial, adequately powered to detect clinical outcomes, is warranted.

[Clinical scores for the risk of bleeding with or without anticoagulation].

Science.gov (United States)

Junod, Alain

2016-09-14

The assessment of hemorragic risk related to therapeutic anticoagulation is made difficult because of the variety of existing drugs, the heterogeneity of treatment strategies and their duration. Six prognostic scores have been analyzed. For three of them, external validations have revealed a marked decrease in the discrimination power. One British study, Qbleed, based on the data of more than 1 million of ambulatory patients, has repeatedly satisfied quality criteria. Two scores have also studied the bleeding risk during hospital admission for acute medical disease. The development of new and effective anticoagulants with fewer side-effects is more likely to solve this problem than the production of new clinical scores.

Human Milk Glycoproteins Protect Infants Against Human Pathogens

Science.gov (United States)

Liu, Bo

2013-01-01

Abstract Breastfeeding protects the neonate against pathogen infection. Major mechanisms of protection include human milk glycoconjugates functioning as soluble receptor mimetics that inhibit pathogen binding to the mucosal cell surface, prebiotic stimulation of gut colonization by favorable microbiota, immunomodulation, and as a substrate for bacterial fermentation products in the gut. Human milk proteins are predominantly glycosylated, and some biological functions of these human milk glycoproteins (HMGPs) have been reported. HMGPs range in size from 14 kDa to 2,000 kDa and include mucins, secretory immunoglobulin A, bile salt-stimulated lipase, lactoferrin, butyrophilin, lactadherin, leptin, and adiponectin. This review summarizes known biological roles of HMGPs that may contribute to the ability of human milk to protect neonates from disease. PMID:23697737

Bleeding complications during anticoagulant treatment in patients with cancer

NARCIS (Netherlands)

Kamphuisen, Pieter W.; Beyer-Westendorf, Jan

Patients with cancer have an increased risk of bleeding complications, of which some are fatal. This risk is influenced by chemotherapy, cancer type and stage, thrombocytopenia, renal function, and previous bleeding. Since many cancer patients receive anticoagulant treatment for prophylaxis or

Self-management of oral anticoagulant therapy in two centers

DEFF Research Database (Denmark)

Nilsson, Hanna; Grove, E; Larsen, Torben Bjerregaard

of Cardiology, Aarhus University Hospital, Aarhus; 3Department of Cardiology, Aalborg Hospital & Department of Health Science and Technology, Aalborg University, Aalborg, Denmark haana_86@hotmail.com Objectives: Patient-self-management (PSM) of oral anticoagulant therapy with vitamin K antagonists have...

Phage Display Breast Carcinoma cDNA Libraries: Isolation of Clones Which Specifically Bind to Membrane Glycoproteins, Mucins, and Endothelial Cell Surface

National Research Council Canada - National Science Library

Yamamoto, Fumiichiro

2000-01-01

.... Using blood- group H-expressing glycoprotein fraction as bait, we observed enrichment of phage clones expressing sequences from galectin-3, a lectin with an affinity with the blood-group substance...

Synthesis of Fucosylated Chondroitin Sulfate Glycoclusters: A Robust Route to New Anticoagulant Agents.

Science.gov (United States)

Zhang, Xiao; Yao, Wang; Xu, Xiaojiang; Sun, Huifang; Zhao, Jinhua; Meng, Xiangbao; Wu, Mingyi; Li, Zhongjun

2018-02-01

Fucosylated chondroitin sulfate (FuCS) is a structurally distinct glycosaminoglycan with excellent anticoagulant activity. Studies show that FuCS and its depolymerized fragments exhibit a different anticoagulant mechanism from that of heparin derivatives, with decreased risks of adverse effects and bleeding. However, further exploitation has been hindered by the scarcity of structurally defined oligosaccharides. Herein, facile method is reported for the synthesis of the repeating trisaccharide unit of FuCS based on the degradation of chondroitin sulfate polymers. A series of simplified FuCS glycomimetics that have highly tunable structures, controllable branches, and defined sulfation motifs were generated by copper-catalyzed alkyne-azide cycloaddition. Remarkable improvement in activated partial thromboplastin time (APTT) assay activities was observed as the branches increased, but no significant influences were observed for prothrombin time (PT) and thrombin time (TT) assay activities. Further FXase inhibition tests suggested that glycoclusters 33 b-40 b selectively inhibited intrinsic anticoagulant activities, but had little effect on the extrinsic and common coagulation pathways. Notably, glycoclusters with the 2,4-di-O-sulfated fucosyl residue displayed the most potency, which was in consistent with that of natural polysaccharides. These FuCS clusters demonstrated potency to mimic linear glycosaminoglycans and offer a new framework for the development of novel anticoagulant agents. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantitative mass spectrometric analysis of glycoproteins combined with enrichment methods.

Science.gov (United States)

Ahn, Yeong Hee; Kim, Jin Young; Yoo, Jong Shin

2015-01-01

Mass spectrometry (MS) has been a core technology for high sensitive and high-throughput analysis of the enriched glycoproteome in aspects of quantitative assays as well as qualitative profiling of glycoproteins. Because it has been widely recognized that aberrant glycosylation in a glycoprotein may involve in progression of a certain disease, the development of efficient analysis tool for the aberrant glycoproteins is very important for deep understanding about pathological function of the glycoprotein and new biomarker development. This review first describes the protein glycosylation-targeting enrichment technologies mainly employing solid-phase extraction methods such as hydrizide-capturing, lectin-specific capturing, and affinity separation techniques based on porous graphitized carbon, hydrophilic interaction chromatography, or immobilized boronic acid. Second, MS-based quantitative analysis strategies coupled with the protein glycosylation-targeting enrichment technologies, by using a label-free MS, stable isotope-labeling, or targeted multiple reaction monitoring (MRM) MS, are summarized with recent published studies. © 2014 The Authors. Mass Spectrometry Reviews Published by Wiley Periodicals, Inc.

Basigin (CD147), a multifunctional transmembrane glycoprotein with various binding partners.

Science.gov (United States)

Muramatsu, Takashi

2016-05-01

Basigin, also called CD147 or EMMPRIN, is a transmembrane glycoprotein that belongs to the immunoglobulin superfamily. Basigin has isoforms; the common form (basigin or basigin-2) has two immunoglobulin domains, and the extended form (basigin-1) has three. Basigin is the receptor for cyclophilins, S100A9 and platelet glycoprotein VI, whereas basigin-1 serves as the receptor for the rod-derived cone viability factor. Basigin tightly associates with monocarboxylate transporters and is essential for their cell surface translocation and activities. In the same membrane plane, basigin also associates with other proteins including GLUT1, CD44 and CD98. The carbohydrate portion of basigin is recognized by lectins, such as galectin-3 and E-selectin. These molecular recognitions form the basis for the role of basigin in the transport of nutrients, migration of inflammatory leukocytes and induction of matrix metalloproteinases. Basigin is important in vision, spermatogenesis and other physiological phenomena, and plays significant roles in the pathogenesis of numerous diseases, including cancer. Basigin is also the receptor for an invasive protein RH5, which is present in malaria parasites. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society.

A Method for Determining the Content of Glycoproteins in Biological Samples

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Yang Gao

2016-11-01

Full Text Available The glycoprotein purified from the mycelium extract of Tremella fuciformis was marked with iodine through the iodine substitution reaction. The content of iodine, which is indicative of the amount of the marked tremella glycoprotein (ITG, was detected with Inductively coupled plasma mass spectrometry (ICP-MS. The method was found to be stable, sensitive, and accurate at detecting the content of iodine-substituted glycoprotein, and was used in the quantitative analysis of biological samples, including blood and organs. Different biological samples were collected from rats after oral administration of ITG, and were tested for iodine content by ICP-MS to calculate the amount of ITG in the samples. The results suggested that ICP-MS is a sensitive, stable, and accurate method for detection of iodinated glycoproteins in blood and organs.

Quality of Vitamin K Antagonist Anticoagulation in Spain: Prevalence of Poor Control and Associated Factors.

Science.gov (United States)

Anguita Sánchez, Manuel; Bertomeu Martínez, Vicente; Cequier Fillat, Ángel

2015-09-01

To study the prevalence of poorly controlled vitamin K antagonist anticoagulation in Spain in patients with nonvalvular atrial fibrillation, and to identify associated factors. We studied 1056 consecutive patients seen at 120 cardiology clinics in Spain between November 2013 and March 2014. We analyzed the international normalized ratio from the 6 months prior to the patient's visit, calculating the prevalence of poorly controlled anticoagulation, defined as < 65% time in therapeutic range using the Rosendaal method. Mean age was 73.6 years (standard deviation, 9.8 years); women accounted for 42% of patients. The prevalence of poorly controlled anticoagulation was 47.3%. Mean time in therapeutic range was 63.8% (25.9%). The following factors were independently associated with poorly controlled anticoagulation: kidney disease (odds ratio = 1.53; 95% confidence interval, 1.08-2.18; P = .018), routine nonsteroidal anti-inflammatory drugs (odds ratio = 1.79; 95% confidence interval, 1.20-2.79; P = .004), antiplatelet therapy (odds ratio = 2.16; 95% confidence interval, 1.49-3.12; P < .0001) and absence of angiotensin receptor blockers (odds ratio = 1.39; 95% confidence interval, 1.08-1.79; P = .011). There is a high prevalence of poorly controlled vitamin K antagonist anticoagulation in Spain. Factors associated with poor control are kidney disease, routine nonsteroidal anti-inflammatory drugs, antiplatelet use, and absence of angiotensin receptor blockers. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Selective interaction of heparin with the variable region 3 within surface glycoprotein of laboratory-adapted feline immunodeficiency virus.

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Qiong-Ying Hu

Full Text Available Heparan sulfate proteoglycans (HSPG can act as binding receptors for certain laboratory-adapted (TCA strains of feline immunodeficiency virus (FIV and human immunodeficiency virus (HIV. Heparin, a soluble heparin sulfate (HS, can inhibit TCA HIV and FIV entry mediated by HSPG interaction in vitro. In the present study, we further determined the selective interaction of heparin with the V3 loop of TCA of FIV. Our current results indicate that heparin selectively inhibits infection by TCA strains, but not for field isolates (FS. Heparin also specifically interferes with TCA surface glycoprotein (SU binding to CXCR4, by interactions with HSPG binding sites on the V3 loop of the FIV envelope protein. Peptides representing either the N- or C-terminal side of the V3 loop and containing HSPG binding sites were able to compete away the heparin block of TCA SU binding to CXCR4. Heparin does not interfere with the interaction of SU with anti-V3 antibodies that target the CXCR4 binding region or with the interaction between FS FIV and anti-V3 antibodies since FS SU has no HSPG binding sites within the HSPG binding region. Our data show that heparin blocks TCA FIV infection or entry not only through its competition of HSPG on the cell surface interaction with SU, but also by its interference with CXCR4 binding to SU. These studies aid in the design and development of heparin derivatives or analogues that can inhibit steps in virus infection and are informative regarding the HSPG/SU interaction.

Vitamin K and stability of oral anticoagulant therapy

NARCIS (Netherlands)

Rombouts, Eva Karolien

2011-01-01

One of the causes of unstable anticoagulation is a variable vitamin K intake. The main objective of this thesis was to test the hypothesis that the INR is particularly sensitive to changes in vitamin K intake when vitamin K status is low, and that patients with a low vitamin K intake would therefore

Non-vitamin K antagonist oral anticoagulants (NOAC) in the treatment of venous thromboembolism

OpenAIRE

Sebastian Werth; Jan Beyer-Westendorf

2015-01-01

In case of venous thromboembolism (VTE) e ective anticoagulation is needed. The introduction of non-vitamin K antagonist oral anticoagulants (NOACs) for VTE therapy o ers new treatment options and, in general, simpli es VTE therapy compared to the concept of LMWH/ VKA. At the same time, NOACs may help to improve the clinical outcome of patients with VTE as trial results consistently indicated the reduction in major bleeding complications. There are several reasons to use NOAC in special p...

Diagnostic imaging of severe rectus sheath hematoma complicating anticoagulant therapy

International Nuclear Information System (INIS)

Blum, A.; Bui, P.; Boccaccini, H.; Bresler, L.; Claudon, M.; Boissel, P.; Regent, D.

1995-01-01

CT were performed in thirteen patients (12 women, 1 man) aged from 53 to 90 (mean age, 74) with severe RSH. Five patients also underwent ultrasound examination and three MR examination. Nine patients (69%) were receiving subcutaneous injection of heparin, three (23%) oral anticoagulant therapy and one continuous IV infusion of heparin. Clinical diagnosis was reached in 6 cases. Excessive activity of anticoagulant therapy was noted in 4 cases. The location of the RSH, their densities and their signals were analysed. All the RSH were mostly developed in the lower third of the abdominal wall, had a large spreading into the Retzius space and compressed the bladder and/or the bowels. RSH were all hyperdense and in 8 cases (61%) a fluid-fluid level due to the hematocrit effect was noted. In one case, a retroperitoneal hematoma was discovered. The extension of the RSH was well delineated with MRI. The RSH showed itself with heterogeneous signal intensities with areas of high-signal-intensity on T1-weighted images. Fluid-fluid levels and a concentric ring sign were also noted. Older women with subcutaneous injection of heparin are especially prone to RSH even though there is no overall excessive activity of anticoagulant therapy. Clinical and biological diagnosis may be difficult. CT scan is the exam of choice to reach a precise and acute diagnosis of RSH. (authors). 34 refs., 8 figs

Renal Infarction during Anticoagulant Therapy after Living Donor Liver Transplantation

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Shinji Onda

2018-04-01

Full Text Available Introduction: Liver transplant recipients are at risk for complications of vascular thrombosis. The reconstructed hepatic artery and portal vein thrombosis potentially result in hepatic failure and graft loss. Renal infarction is a rare clinical condition, but in severe cases, it may lead to renal failure. We herein report a case of renal infarction after living donor liver transplantation (LDLT during anticoagulant therapy. Case Presentation: A 60-year-old woman with end-stage liver disease due to primary biliary cholangitis underwent LDLT with splenectomy. Postoperatively, tacrolimus, mycophenolate mofetil, and steroid were used for initial immunosuppression therapy. On postoperative day (POD 5, enhanced computed tomography (CT revealed splenic vein thrombosis, and anticoagulant therapy with heparin followed by warfarin was given. Follow-up enhanced CT on POD 20 incidentally demonstrated right renal infarction. The patient’s renal function was unchanged and the arterial flow was good, and the splenic vein thrombosis resolved. At 4 months postoperatively, warfarin was discontinued, but she developed recurrent splenic vein thrombosis 11 months later, and warfarin was resumed. As of 40 months after transplantation, she discontinued warfarin and remains well without recurrence of splenic vein thrombosis or renal infarction. Conclusion: Renal infarction is a rare complication of LDLT. In this case, renal infarction was incidentally diagnosed during anticoagulant therapy and was successfully treated.

Glycoprotein of the wall of sycamore tissue-culture cells.

Science.gov (United States)

Heath, M F; Northcote, D H

1971-12-01

1. A glycoprotein containing a large amount of hydroxyproline is present in the cell walls of sycamore callus cells. This protein is insoluble and remained in the alpha-cellulose when a mild separation procedure was used to obtain the polysaccharide fractions of the wall. The glycoprotein contained a high proportion of arabinose and galactose. 2. Soluble glycopeptides were prepared from the alpha-cellulose fraction when peptide bonds were broken by hydrazinolysis. The soluble material was fractionated by gel filtration and one glycopeptide was further purified by electrophoresis; it had a composition of 10% hydroxyproline, 35% arabinose and 55% galactose, and each hydroxyproline residue carried a glycosyl radical so that the oligosaccharides on the glycopeptide had an average degree of polymerization of 9. 3. The extraction of the glycopeptides was achieved without cleavage of glycosyl bonds, so that the glycoprotein cannot act as a covalent cross-link between the major polysaccharides of the wall. 4. The wall protein approximates in conformation to polyhydroxyproline and therefore it probably has similar physicochemical properties to polyhydroxyproline. This is discussed in relation to the function of the glycoprotein and its effect on the physical and chemical nature of the wall.

Global identification of prokaryotic glycoproteins based on an Escherichia coli proteome microarray.

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Zong-Xiu Wang

Full Text Available Glycosylation is one of the most abundant protein posttranslational modifications. Protein glycosylation plays important roles not only in eukaryotes but also in prokaryotes. To further understand the roles of protein glycosylation in prokaryotes, we developed a lectin binding assay to screen glycoproteins on an Escherichia coli proteome microarray containing 4,256 affinity-purified E.coli proteins. Twenty-three E.coli proteins that bound Wheat-Germ Agglutinin (WGA were identified. PANTHER protein classification analysis showed that these glycoprotein candidates were highly enriched in metabolic process and catalytic activity classes. One sub-network centered on deoxyribonuclease I (sbcB was identified. Bioinformatics analysis suggests that prokaryotic protein glycosylation may play roles in nucleotide and nucleic acid metabolism. Fifteen of the 23 glycoprotein candidates were validated by lectin (WGA staining, thereby increasing the number of validated E. coli glycoproteins from 3 to 18. By cataloguing glycoproteins in E.coli, our study greatly extends our understanding of protein glycosylation in prokaryotes.

Emergency management of major bleeding in a case of maxillofacial trauma and anticoagulation: utility of prothrombin complex concentrates in the shock room

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Alessandro Morotti

2015-03-01

Full Text Available Life-threatening bleeding in anticoagulation with Warfarin is an emergency challenging issue. Several approaches are available to treat bleeding in either over-anticoagulation or propeanticoagulation, including vitamin K, fresh frozen plasma and prothrombin complex concentrates (PCC administration. In coexisting trauma-induced bleeding and anticoagulation, reversal of anticoagulation must be a rapid and highly effective procedure. Furthermore the appropriate treatment must be directly available in each shock rooms to guarantee the rapid management of the emergency. PCC require a simple storage, rapid accessibility, fast administration procedures and high effectiveness. Here we report the utility of PCC in management of a craniofacial trauma in proper-anticoagulation.

Thyroid hormone upregulates zinc-α2-glycoprotein production in the liver but not in adipose tissue.

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Rafael Simó

Full Text Available Overproduction of zinc-α2-glycoprotein by adipose tissue is crucial in accounting for the lipolysis occurring in cancer cachexia of certain malignant tumors. The main aim of this study was to explore whether thyroid hormone could enhance zinc-α2-glycoprotein production in adipose tissue. In addition, the regulation of zinc-α2-glycoprotein by thyroid hormone in the liver was investigated. We performed in vitro (HepG2 cells and primary human adipocytes and in vivo (C57BL6/mice experiments addressed to examine the effect of thyroid hormone on zinc-α2-glycoprotein production (mRNA and protein levels in liver and visceral adipose tissue. We also measured the zinc-α2-glycoprotein serum levels in a cohort of patients before and after controlling their hyperthyroidism. Our results showed that thyroid hormone up-regulates zinc-α2-glycoprotein production in HepG2 cells in a dose-dependent manner. In addition, the zinc-α2-glycoprotein proximal promoter contains functional thyroid hormone receptor binding sites that respond to thyroid hormone treatment in luciferase reporter gene assays in HepG2 cells. Furthermore, zinc-α2-glycoprotein induced lipolysis in HepG2 in a dose-dependent manner. Our in vivo experiments in mice confirmed the up-regulation of zinc-α2-glycoprotein induced by thyroid hormone in the liver, thus leading to a significant increase in zinc-α2-glycoprotein circulating levels. However, thyroid hormone did not regulate zinc-α2-glycoprotein production in either human or mouse adipocytes. Finally, in patients with hyperthyroidism a significant reduction of zinc-α2-glycoprotein serum levels was detected after treatment but was unrelated to body weight changes. We conclude that thyroid hormone up-regulates the production of zinc-α2-glycoprotein in the liver but not in the adipose tissue. The neutral effect of thyroid hormones on zinc-α2-glycoprotein expression in adipose tissue could be the reason why zinc-α2-glycoprotein is not

Thyroid hormone upregulates zinc-α2-glycoprotein production in the liver but not in adipose tissue.

Science.gov (United States)

Simó, Rafael; Hernández, Cristina; Sáez-López, Cristina; Soldevila, Berta; Puig-Domingo, Manel; Selva, David M

2014-01-01

Overproduction of zinc-α2-glycoprotein by adipose tissue is crucial in accounting for the lipolysis occurring in cancer cachexia of certain malignant tumors. The main aim of this study was to explore whether thyroid hormone could enhance zinc-α2-glycoprotein production in adipose tissue. In addition, the regulation of zinc-α2-glycoprotein by thyroid hormone in the liver was investigated. We performed in vitro (HepG2 cells and primary human adipocytes) and in vivo (C57BL6/mice) experiments addressed to examine the effect of thyroid hormone on zinc-α2-glycoprotein production (mRNA and protein levels) in liver and visceral adipose tissue. We also measured the zinc-α2-glycoprotein serum levels in a cohort of patients before and after controlling their hyperthyroidism. Our results showed that thyroid hormone up-regulates zinc-α2-glycoprotein production in HepG2 cells in a dose-dependent manner. In addition, the zinc-α2-glycoprotein proximal promoter contains functional thyroid hormone receptor binding sites that respond to thyroid hormone treatment in luciferase reporter gene assays in HepG2 cells. Furthermore, zinc-α2-glycoprotein induced lipolysis in HepG2 in a dose-dependent manner. Our in vivo experiments in mice confirmed the up-regulation of zinc-α2-glycoprotein induced by thyroid hormone in the liver, thus leading to a significant increase in zinc-α2-glycoprotein circulating levels. However, thyroid hormone did not regulate zinc-α2-glycoprotein production in either human or mouse adipocytes. Finally, in patients with hyperthyroidism a significant reduction of zinc-α2-glycoprotein serum levels was detected after treatment but was unrelated to body weight changes. We conclude that thyroid hormone up-regulates the production of zinc-α2-glycoprotein in the liver but not in the adipose tissue. The neutral effect of thyroid hormones on zinc-α2-glycoprotein expression in adipose tissue could be the reason why zinc-α2-glycoprotein is not related to weight

Safety of percutaneous nephrolithotomy in patients on chronic anticoagulant or antiplatelet therapy.

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Fernández-Baltar, C; Pérez-Fentes, D; Sánchez-García, J F; García-Freire, C

2018-01-22

In developed countries, the incidence of cardiovascular disease is increasing, therefore, anticoagulant and antiplatelet drugs are a widespread treatment nowadays. Percutaneous nephrolithotomy (PNL) is the first-line treatment for large or complex stones (> 2 cm) and remains an alternative for the smaller ones. The objective of this study is to analyze whether PNL surgery is a safe procedure in patients under a treatment discontinuation protocol for anticoagulant or antiplatelet therapies. We retrospectively studied 301 patients who underwent PNL in our hospital between 2008 and 2016 and identified 46 patients on chronic antiplatelet or anticoagulation treatment. With respect to PNL outcomes, the stone-free rate was similar (78 vs 74%, p = 0.762) in both groups, without any significant differences in the overall postoperative complications (17 vs 26%, p = 0.203). The incidence of hemorrhagic complications was similar between groups (12 vs 9%, p = 0.492), as demonstrated by the mean drop in hemoglobin (Hb), which was comparable in both cohorts (2.2 ± 1.3 vs 2.0 ± 1.4 p = 0.270) and the blood transfusion rate (14% in group A and 8% in group B, p = 0.205). No thromboembolic events were found within the year after the PNL procedure. PNL is a safe and effective intervention in patients under a treatment discontinuation protocol for anticoagulant or antiplatelet therapies. Although our study demonstrates the feasibility of this protocol, new scientific evidence aims to stratify the thromboembolic and bleeding risk of each patient to individualize the perioperative management thereafter.

Target specific oral anticoagulants in the management of thromboembolic disease in the elderly.

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Maddula, Surekha; Ansell, Jack

2013-08-01

The elderly population represents a population at highest risk of thromboembolism, but also the most vulnerable to hemorrhage. In the community setting there is a general tendency to under- treat this patient group. Specific consideration must be taken with elderly patients because they have reduced renal function, co-morbidities and risk of falls, altered pharmacodynamics, and challenges with adherence. Vitamin K antagonists, most often warfarin, have been the first line choice of therapy for long-term anticoagulation and enjoyed an unopposed position in the market for the last 70 years. Recently several new oral anticoagulants have been developed and found to be equally effective as warfarin in phase III studies and may provide an optimal treatment option in the elderly population. In this review we explore the target-specific oral anticoagulants and the pharmacological differences between them with a focus on the elderly population in whom these new drugs would constitute a possible alternative to warfarin therapy.

The "Janus face" of the thrombin binding aptamer: Investigating the anticoagulant and antiproliferative properties through straightforward chemical modifications.

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Esposito, Veronica; Russo, Annapina; Amato, Teresa; Vellecco, Valentina; Bucci, Mariarosaria; Mayol, Luciano; Russo, Giulia; Virgilio, Antonella; Galeone, Aldo

2018-02-01

The thrombin binding aptamer (TBA) is endowed with both anticoagulant and antiproliferative activities. Its chemico-physical and/or biological properties can be tuned by the site-specific replacement of selected residues. Four oligodeoxynucleotides (ODNs) based on the TBA sequence (5'-GGTTGGTGTGGTTGG-3') and containing 2'-deoxyuridine (U) or 5-bromo-2'-deoxyuridine (B) residues at positions 4 or 13 have been investigated by NMR and CD techniques. Furthermore, their anticoagulant (PT assay) and antiproliferative properties (MTT assay) have been tested and compared with two further ODNs containing 5-hydroxymethyl-2'-deoxyuridine (H) residues in the same positions, previously investigated. The CD and NMR data suggest that all the investigated ODNs are able to form G-quadruplexes strictly resembling that of TBA. The introduction of B residues in positions 4 or 13 increases the melting temperature of the modified aptamers by 7 °C. The replacement of thymidines with U in the same positions results in an enhanced anticoagulant activity compared to TBA, also at low ODN concentration. Although all ODNs show antiproliferative properties, only TBA derivatives containing H in the positions 4 and 13 lose the anticoagulant activity and remarkably preserve the antiproliferative one. All ODNs have shown antiproliferative activities against two cancer cell lines but only those with U and B are endowed with anticoagulant activities similar or improved compared to TBA. The appropriate site-specific replacement of the residues in the TT loops of TBA with commercially available thymine analogues is a useful strategy either to improve the anticoagulant activity or to preserve the antiproliferative properties by quenching the anticoagulant ones. Copyright © 2017 Elsevier Inc. All rights reserved.

3,3′,4,4′,5-Pentachlorobiphenyl Inhibits Drug Efflux Through P-Glycoprotein in KB-3 Cells Expressing Mutant Human P-Glycoprotein

Directory of Open Access Journals (Sweden)

Hiroshi Fujise

2004-01-01

Full Text Available The effects on the drug efflux of 3,3′,4,4′,5-pentachlorobiphenyl (PCB-126, the most toxic of all coplanar polychlorinated biphenyls (Co-PCBs, were examined in KB-3 cells expressing human wild-type and mutant P-glycoprotein in which the 61st amino acid was substituted for serine or phenylalanine (KB3-Phe61. In the cells expressing P-glycoproteins, accumulations of vinblastine and colchicine decreased form 85% to 92% and from 62% to 91%, respectively, and the drug tolerances for these chemicals were increased. In KB3-Phe61, the decreases in drug accumulation were inhibited by adding PCB-126 in a way similar to that with cyclosporine A: by adding 1 μM PCB-126, the accumulations of vinblastine and colchicine increased up to 3.3- and 2.3-fold, respectively. It is suggested that PCB-126 decreased the drug efflux by inhibiting the P-glycoprotein in KB3-Phe61. Since there were various P-glycoproteins and many congeners of Co-PCBs, this inhibition has to be considered a new cause of the toxic effects of Co-PCBs.

Medium intensity oral anticoagulants versus aspirin after cerebral ischaemia of arterial origin (ESPRIT): a randomised controlled trial.

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Halkes, P H A; van Gijn, J; Kappelle, L J; Koudstaal, P J; Algra, A

2007-02-01

Oral anticoagulants are better than aspirin for secondary prevention after myocardial infarction and after cerebral ischaemia in combination with non-rheumatic atrial fibrillation. The European/Australasian Stroke Prevention in Reversible Ischaemia Trial (ESPRIT) aimed to determine whether oral anticoagulation with medium intensity is more effective than aspirin in preventing future vascular events in patients with transient ischaemic attack or minor stroke of presumed arterial origin. In this international, multicentre trial, patients were randomly assigned within 6 months after a transient ischaemic attack or minor stroke of presumed arterial origin either anticoagulants (target INR range 2.0-3.0; n=536) or aspirin (30-325 mg daily; n=532). The primary outcome was the composite of death from all vascular causes, non-fatal stroke, non-fatal myocardial infarction, or major bleeding complication, whichever occurred first. In a post hoc analysis anticoagulants were compared with the combination of aspirin and dipyridamole (200 mg twice daily). Treatment was open, but auditing of outcome events was blinded. Primary analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial (number ISRCTN73824458) and with ClinicalTrials.gov (NCT00161070). The anticoagulants versus aspirin comparison of ESPRIT was prematurely ended because ESPRIT reported previously that the combination of aspirin and dipyridamole was more effective than aspirin alone. Mean follow-up was 4.6 years (SD 2.2). The mean achieved INR was 2.57 (SD 0.86). A primary outcome event occurred in 99 (19%) patients on anticoagulants and in 98 (18%) patients on aspirin (hazard ratio [HR] 1.02, 95% CI 0.77-1.35). The HR for ischaemic events was 0.73 (0.52-1.01) and for major bleeding complications 2.56 (1.48-4.43). The HR for the primary outcome event comparing anticoagulants with the combination treatment of aspirin and dipyridamole was 1.31 (0.98-1.75). Oral

BoHV-4-based vector delivering Ebola virus surface glycoprotein

Directory of Open Access Journals (Sweden)

Alfonso Rosamilia

2016-11-01

Full Text Available Abstract Background Ebola virus (EBOV is a Category A pathogen that is a member of Filoviridae family that causes hemorrhagic fever in humans and non-human primates. Unpredictable and devastating outbreaks of disease have recently occurred in Africa and current immunoprophylaxis and therapies are limited. The main limitation of working with pathogens like EBOV is the need for costly containment. To potentiate further and wider opportunity for EBOV prophylactics and therapies development, innovative approaches are necessary. Methods In the present study, an antigen delivery platform based on a recombinant bovine herpesvirus 4 (BoHV-4, delivering a synthetic EBOV glycoprotein (GP gene sequence, BoHV-4-syEBOVgD106ΔTK, was generated. Results EBOV GP was abundantly expressed by BoHV-4-syEBOVgD106ΔTK transduced cells without decreasing viral replication. BoHV-4-syEBOVgD106ΔTK immunized goats produced high titers of anti-EBOV GP antibodies and conferred a long lasting (up to 6 months, detectable antibody response. Furthermore, no evidence of BoHV-4-syEBOVgD106ΔTK viremia and secondary localization was detected in any of the immunized animals. Conclusions The BoHV-4-based vector approach described here, represents: an alternative antigen delivery system for vaccination and a proof of principle study for anti-EBOV antibodies generation in goats for potential immunotherapy applications.

Prediction of conserved sites and domains in glycoproteins B, C and D of herpes viruses.

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Rasheed, Muhammad Asif; Ansari, Abdur Rahman; Ihsan, Awais; Navid, Muhammad Tariq; Ur-Rehman, Shahid; Raza, Sohail

2018-03-01

Glycoprotein B (gB), C (gC) and D (gD) of herpes simplex virus are implicated in virus adsorption and penetration. The gB, gC and gD are glycoproteins for different processes of virus binding and attachment to the host cells. Moreover, their expression is necessary and sufficient to induce cell fusion in the absence of other glycoproteins. Egress of herpes simplex virus (HSV) and other herpes viruses from cells involves extensive modification of cellular membranes and sequential envelopment, de-envelopment and re-envelopment steps. Viral glycoproteins are important in these processes, and frequently two or more glycoproteins can largely suffice in any step. Hence, we target the 3 important glycoproteins (B, C and D) of eight different herpes viruses of different species. These species include human (HSV1 and 2), bovine (BHV1), equine (EHV1 and 4), chicken (ILT1 and MDV2) and pig (PRV1). By applying different bioinformatics tools, we highlighted the conserved sites in these glycoproteins which might be most significant regarding attachment and infection of the viruses. Moreover the conserved domains in these glycoproteins are also highlighted. From this study, we will able to analyze the role of different viral glycoproteins of different species during herpes virus adsorption and penetration. Moreover, this study will help to construct the antivirals that target the glycoproteins of different herpes viruses. Copyright © 2018 Elsevier Ltd. All rights reserved.

A survey of anticoagulation practice among German speaking microsurgeons – Perioperative management of anticoagulant therapy in free flap surgery [Erhebung über die antikoagulatorische Praxis unter deutschsprachigen Mikrochirurgen – Perioperatives Management der antikoagulatorischen Therapie bei freien Lappentransplantaten

Directory of Open Access Journals (Sweden)

Jokuszies, Andreas

2012-02-01

Full Text Available [english] Background: Anticoagulation is a crucial element in microsurgery. Although various clinical studies and international surveys have revealed that anticoagulation strategies can vary and result in similar outcomes, anticoagulative regimen are far away from standardization. In Germany and german speaking countries standardized anticoagulation protocols concerning free flap surgery do not exist so far. Methods: To evaluate the current practice of clinics in Germany, Austria and Switzerland with specialization in microsurgery we performed a questionnaire surveying the perioperative regimen of anticoagulant and antiplatelet therapy in free flap surgery. The microsurgeons were interrogated on several anticoagulant, rheologic and antiplatelet medications, their dosage and perioperative frequency of application pre-, intra- and postoperative.Results: The questionnaire revealed that the used antithrombotic and perioperative regimens varied from department to department presumably based on the personal experience of the surgeon. Multiple approaches are used with a wide range of anticoagulants used either alone or in combination, with different intervals of application and different dosages. Conclusion: Therefore consensus meetings should be held in future leading to conduct prospective multicenter studies with formulation of standardized anticoagulative and perioperative protocols in microsurgery reducing flap failure to other than pharmacologic reasons.[german] Hintergrund: Die Antikoagulation stellt ein zentrales Element in der Mikrochirurgie dar. Zahlreiche klinische Studien und internationale Erhebungen zu antikoagulatorischen Strategien weisen eine grosse Varianz bei vergleichbaren Resultaten nach, entbehren jedoch einer Standardisierung. Auch in Deutschland und deutschsprachigen Ländern fehlen bislang standardisierte Regime zur Antikoagulation in der Mikrochirurgie.Methodik: Zur Erhebung der antikoagulatorischen Praxis unter

Shifting to a non-vitamin K antagonist oral anticoagulation agent from vitamin K antagonist in atrial fibrillation

DEFF Research Database (Denmark)

Fosbøl, Emil L; Vinding, Naja Emborg; Lamberts, Morten

2017-01-01

Aims: After non-vitamin K antagonist (VKA) oral anticoagulation agents (NOAC) have been approved for thrombo-embolic prophylaxis in non-valvular atrial fibrillation (NVAF), utilization of oral anticoagulants (OAC) in NVAF has changed. Contemporary shifting from a VKA to a NOAC (dabigatran...

In vitro anti-thrombotic and anti-coagulant properties of blacklip abalone (Haliotis rubra) viscera hydrolysate.

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Suleria, Hafiz Ansar Rasul; Masci, Paul P; Addepalli, Rama; Chen, Wei; Gobe, Glenda C; Osborne, Simone A

2017-07-01

Abalone viscera contain sulphated polysaccharides with anti-thrombotic and anti-coagulant activities. In this study, a hydrolysate was prepared from blacklip abalone (Haliotis rubra) viscera using papain and bromelain and fractionated using ion exchange and size exclusion chromatography. Hydrolysates and fractions were investigated for in vitro thrombin inhibition mediated through heparin cofactor II (HCII) as well as anti-coagulant activity in plasma and whole blood. On the basis of sulphated polysaccharide concentration, the hydrolysate inhibited thrombin through HCII with an inhibitor concentration at 50% (IC50) of 16.5 μg/mL compared with 2.1 μg/mL for standard heparin. Fractionation concentrated HCII-mediated thrombin inhibition down to an IC50 of 1.8 μg/mL and improved anti-coagulant activities by significantly delaying clotting time. This study confirmed the presence of anti-thrombotic and anti-coagulant molecules in blacklip abalone viscera and demonstrated that these activities can be enriched with a simple chromatography regime. Blacklip abalone viscera warrant further investigation as a source of nutraceutical or functional food ingredients. Graphical abstract Schematic showing preparation of bioactive extracts and fractions from blacklip abalone.

Autoantibodies

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... Antibodies Beta-2 Glycoprotein 1 Antibodies Antiphospholipid Antibodies (APA) Lupus anticoagulants (LA) Endocrine/metabolic system Diabetes-related ... Timothy J. (2001). Mosby's Diagnostic and Laboratory Test Reference 5th Edition: Mosby, Inc., Saint Louis, MO. What ...

Glycoprotein and proteoglycan techniques

International Nuclear Information System (INIS)

Beeley, J.G.

1985-01-01

The aim of this book is to describe techniques which can be used to answer some of the basic questions about glycosylated proteins. Methods are discussed for isolation, compositional analysis, and for determination of the primary structure of carbohydrate units and the nature of protein-carbohydrate linkages of glycoproteins and proteoglycans. High resolution NMR is considered, as well as radioactive labelling techniques. (Auth.)

HIV-1 envelope glycoprotein

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Caulfield, Michael; Cupo, Albert; Dean, Hansi; Hoffenberg, Simon; King, C. Richter; Klasse, P. J.; Marozsan, Andre; Moore, John P.; Sanders, Rogier W.; Ward, Andrew; Wilson, Ian; Julien, Jean-Philippe

2017-08-22

The present application relates to novel HIV-1 envelope glycoproteins, which may be utilized as HIV-1 vaccine immunogens, and antigens for crystallization, electron microscopy and other biophysical, biochemical and immunological studies for the identification of broad neutralizing antibodies. The present invention encompasses the preparation and purification of immunogenic compositions, which are formulated into the vaccines of the present invention.

Standardisation of the Laboratory Control of Anticoagulant Therapy

African Journals Online (AJOL)

1974-09-11

Sep 11, 1974 ... Anticoagulant therapy with the coumarin group of drugs has been used in clinical practice for more than a quarter of a century. The most widely used form of laboratory control of the treatment is the Quick one-stage prothrom·- bin time. I. This simple test proved to be satisfactory in most cases, but discrepant ...

Factors Affecting Outcome in Treatment of Chronic Subdural Hematoma in ICU Patients: Impact of Anticoagulation.

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Szczygielski, Jacek; Gund, Sina-Maria; Schwerdtfeger, Karsten; Steudel, Wolf-Ingo; Oertel, Joachim

2016-08-01

The use of anticoagulants and older age are the main risk factors for chronic subdural hematoma (CSDH). Because the age of the population and use of anticoagulants are increasing, a growing number of CSDH cases is expected. To address this issue, we analyzed the impact of anticoagulants on postsurgical outcome in patients in the intensive care unit (ICU). Demographic data, coagulation parameters, surgical details, radiologic appearance of hematoma, Glasgow Coma Scale (GCS) score on admission, and Glasgow Outcome Scale (GOS) score on discharge were retrieved and retrospectively analyzed in 98 patients with CSDH treated in the neurosurgical ICU using correlation coefficient tests and multivariate analysis test. Overall outcome was good (GOS score 4 and 5) in 55.1% of patients. Overall mortality was 9.1%. There was a correlation between GCS score on admission and GOS score. There was no correlation between hematoma thickness/radiologic appearance and impaired coagulation. Disturbance in thrombocyte function (usually resulting from aspirin intake) correlated with improved outcome, whereas warfarin-related coagulopathy correlated with poor recovery. Nevertheless, patients with thrombocytopathy presented with better initial GCS scores. Neither hematoma size nor recurrence rate affected the outcome. The size of CSDH was not associated with poor outcome and is not necessarily determined by the use of anticoagulants. Coagulopathy does not rule out a good outcome, but the impact of anticoagulation on treatment results in CSDH varies between the main groups of drugs (warfarin vs. antiplatelet drugs). Patients in good neurologic condition on ICU admission have better chances of recovery. Copyright © 2016 Elsevier Inc. All rights reserved.

Pulsed electric field extraction enhanced anti-coagulant effect of fungal polysaccharide from Jew's ear (Auricularia auricula).

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Li, Changtian; Mao, Xinxin; Xu, Baojun

2013-01-01

As a Chinese herbal medicine, Jew's ear has been known for its anti-coagulant effects. Hence it is worthwhile developing an effective technique to extract active components. To find the optimal extraction condition and to identify the best strain to yield fungal polysaccharide with anti-coagulant activity. Three strains of Jew's ear from Jilin Province, named as 988, DY 18 and FS 02, and three extraction techniques, namely, high intensity pulsed electric fields (HIPEF), microwave-assisted extraction method (MAEM) and ultrasonic-assisted extraction method (UAEM), were applied to optimise the extraction conditions. The crude extracts and polysaccharides were further determined for anti-coagulant activities. All extracts prolonged blood clotting time as compared to reagent control. The HIPEF exhibited the most remarkable effect among the three extraction techniques. The anti-coagulant activities of extracts were enhanced with increasing electric field strength when the field strength reached 24 kV/cm. Current results suggest that the HIPEF technique will be an effective method in the manufacture of bioactive natural polysaccharide. Copyright © 2012 John Wiley & Sons, Ltd.

Anticoagulant and Antiplatelet Prescribing Patterns for Patients with Atrial Fibrillation after Percutaneous Coronary Intervention.

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Woods, Erin A; Ackman, Margaret L; Graham, Michelle M; Koshman, Sheri L; Boswell, Rosaleen M; Barry, Arden R

2016-01-01

Current guidelines recommend triple antithrombotic therapy (TAT), defined as acetylsalicylic acid (ASA), clopidogrel, and warfarin, for patients with nonvalvular atrial fibrillation who have undergone percutaneous coronary intervention with stent implantation. The choice of anticoagulant/antiplatelet therapy in this population is ambiguous and complex, and prescribing patterns are not well documented. To characterize local prescribing patterns for anticoagulant/antiplatelet therapy after percutaneous coronary intervention in patients with nonvalvular atrial fibrillation. A chart review was conducted at a single quaternary cardiology centre. Patients with nonvalvular atrial fibrillation were identified via medical records, and those who underwent percutaneous coronary intervention were identified using a local clinical patient registry. Adult inpatients with nonvalvular atrial fibrillation and a CHADS2 score (based on congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke) of 1 or higher who underwent percutaneous coronary intervention from 2011 to 2013 were included. Patients undergoing cardiovascular surgery or transcatheter aortic valve replacement, those with mechanical devices requiring anticoagulation, and those with an allergy to any component of TAT were excluded. Seventy patients were included. The median age was 75 years, and 52 (74%) were men. At discharge, 30 (43%) were receiving TAT and 27 (39%) were receiving dual antiplatelet therapy (clopidogrel and ASA). No patients received the combination of warfarin and clopidogrel. Among those who received TAT, 90% (19 of 21) who received a bare metal stent had a recommended duration of 1 month, and 75% (6 of 8) who received a drug-eluting stent had a recommended duration of 1 year. Direct-acting oral anticoagulants with 2 antiplatelet drugs were prescribed for 9% (6 of 70) of the patients, and 10% (7 of 70) received ticagrelor and ASA with or without warfarin. Overall, the

The Anticoagulation of Calf Thrombosis (ACT project: study protocol for a randomized controlled trial

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Horner Daniel

2012-04-01

Full Text Available Abstract Background Half of all lower limb deep vein thrombi (DVT in symptomatic ambulatory patients are located in the distal (calf veins. While proximal disease warrants therapeutic anticoagulation to reduce the associated risks, distal DVT often goes untreated. However, a proportion of untreated distal disease will undoubtedly propagate or embolize. Concern also exists that untreated disease could lead to long-term post thrombotic changes. Currently, it is not possible to predict which distal thrombi will develop such complications. Whether these potential risks outweigh those associated with unrestricted anticoagulation remains unclear. The Anticoagulation of Calf Thrombosis (ACT trial aims to compare therapeutic anticoagulation against conservative management for patients with acute symptomatic distal deep vein thrombosis. Methods ACT is a pragmatic, open-label, randomized controlled trial. Adult patients diagnosed with acute distal DVT will be allocated to either therapeutic anticoagulation or conservative management. All patients will undergo 3 months of clinical and assessor blinded sonographic follow-up, followed by 2-year final review. The project will commence initially as an external pilot study, recruiting over a 16-month period at a single center to assess feasibility measures and clinical event rates. Primary outcome measures will assess feasibility endpoints. Secondary clinical outcomes will be collected to gather accurate data for the design of a definitive clinical trial and will include: (1 a composite endpoint combining thrombus propagation to the popliteal vein or above, development of symptomatic pulmonary embolism or sudden death attributable to venous thromboembolic disease; (2 the incidence of major and minor bleeding episodes; (3 the incidence of post-thrombotic leg syndrome at 2 years using a validated screening tool; and (4 the incidence of venous thromboembolism (VTE recurrence at 2 years. Discussion The ACT trial

Assessment of the efficacy of a novel tailored vitamin K dosing regimen in lowering the International Normalised Ratio in over-anticoagulated patients: a randomised clinical trial.

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Kampouraki, Emmanouela; Avery, Peter J; Wynne, Hilary; Biss, Tina; Hanley, John; Talks, Kate; Kamali, Farhad

2017-09-01

Current guidelines advocate using fixed-doses of oral vitamin K to reverse excessive anticoagulation in warfarinised patients who are either asymptomatic or have minor bleeds. Over-anticoagulated patients present with a wide range of International Normalised Ratio (INR) values and response to fixed doses of vitamin K varies. Consequently a significant proportion of patients remain outside their target INR after vitamin K administration, making them prone to either haemorrhage or thromboembolism. We compared the performance of a novel tailored vitamin K dosing regimen to that of a fixed-dose regimen with the primary measure being the proportion of over-anticoagulated patients returning to their target INR within 24 h. One hundred and eighty-one patients with an index INR > 6·0 (asymptomatic or with minor bleeding) were randomly allocated to receive oral administration of either a tailored dose (based upon index INR and body surface area) or a fixed-dose (1 or 2 mg) of vitamin K. A greater proportion of patients treated with the tailored dose returned to within target INR range compared to the fixed-dose regimen (68·9% vs. 52·8%; P = 0·026), whilst a smaller proportion of patients remained above target INR range (12·2% vs. 34·0%; P vitamin K dosing is more accurate than fixed-dose regimen in lowering INR to within target range in excessively anticoagulated patients. © 2017 John Wiley & Sons Ltd.

Crystallization and preliminary X-ray analysis of Chandipura virus glycoprotein G

International Nuclear Information System (INIS)

Baquero, Eduard; Buonocore, Linda; Rose, John K.; Bressanelli, Stéphane; Gaudin, Yves; Albertini, Aurélie A.

2012-01-01

Chandipura virus glycoprotein ectodomain (Gth) was purified and crystallized at pH 7.5. X-ray diffraction data set was collected to a resolution of 3.1 Å. Fusion in members of the Rhabdoviridae virus family is mediated by the G glycoprotein. At low pH, the G glycoprotein catalyzes fusion between viral and endosomal membranes by undergoing a major conformational change from a pre-fusion trimer to a post-fusion trimer. The structure of the G glycoprotein from vesicular stomatitis virus (VSV G), the prototype of Vesiculovirus, has recently been solved in its trimeric pre-fusion and post-fusion conformations; however, little is known about the structural details of the transition. In this work, a soluble form of the ectodomain of Chandipura virus G glycoprotein (CHAV G th ) was purified using limited proteolysis of purified virus; this soluble ectodomain was also crystallized. This protein shares 41% amino-acid identity with VSV G and thus its structure could provide further clues about the structural transition of rhabdoviral glycoproteins induced by low pH. Crystals of CHAV G th obtained at pH 7.5 diffracted X-rays to 3.1 Å resolution. These crystals belonged to the orthorhombic space group P2 1 2 1 2, with unit-cell parameters a = 150.3, b = 228.2, c = 78.8 Å. Preliminary analysis of the data based on the space group and the self-rotation function indicated that there was no trimeric association of the protomers. This unusual oligomeric status could result from the presence of fusion intermediates in the crystal

Synthetic glycopeptides and glycoproteins with applications in biological research

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Ulrika Westerlind

2012-05-01

Full Text Available Over the past few years, synthetic methods for the preparation of complex glycopeptides have been drastically improved. The need for homogenous glycopeptides and glycoproteins with defined chemical structures to study diverse biological phenomena further enhances the development of methodologies. Selected recent advances in synthesis and applications, in which glycopeptides or glycoproteins serve as tools for biological studies, are reviewed. The importance of specific antibodies directed to the glycan part, as well as the peptide backbone has been realized during the development of synthetic glycopeptide-based anti-tumor vaccines. The fine-tuning of native chemical ligation (NCL, expressed protein ligation (EPL, and chemoenzymatic glycosylation techniques have all together enabled the synthesis of functional glycoproteins. The synthesis of structurally defined, complex glycopeptides or glyco-clusters presented on natural peptide backbones, or mimics thereof, offer further possibilities to study protein-binding events.

Personalized prophylactic anticoagulation decision analysis in patients with membranous nephropathy

Science.gov (United States)

Lee, Taewoo; Biddle, Andrea K.; Lionaki, Sofia; Derebail, Vimal K.; Barbour, Sean J.; Tannous, Sameer; Hladunewich, Michelle A.; Hu, Yichun; Poulton, Caroline J.; Mahoney, Shannon L.; Jennette, J. Charles; Hogan, Susan L.; Falk, Ronald J.; Cattran, Daniel C.; Reich, Heather N.; Nachman, Patrick H.

2014-01-01

Primary membranous nephropathy is associated with increased risk of venous thromboembolic events, which are inversely correlated with serum albumin levels. To evaluate the potential benefit of prophylactic anticoagulation (venous thromboembolic events prevented) relative to the risk (major bleeds), we constructed a Markov decision model. The venous thromboembolic event risk according to serum albumin was obtained from an inception cohort of 898 patients with primary membranous nephropathy. Risk estimates of hemorrhage were obtained from a systematic literature review. Benefit-to-risk ratios were predicted according to bleeding risk and serum albumin. This ratio increased with worsening hypoalbuminemia from 4.5:1 for an albumin under 3 g/dl to 13.1:1 for an albumin under 2 g/dl in patients at low bleeding risk. Patients at intermediate bleeding risk with an albumin under 2 g/dl have a moderately favorable benefit-to-risk ratio (under 5:1). Patients at high bleeding risk are unlikely to benefit from prophylactic anticoagulation regardless of albuminemia. Probabilistic sensitivity analysis, to account for uncertainty in risk estimates, confirmed these trends. From these data, we constructed a tool to estimate the likelihood of benefit based on an individual’s bleeding risk profile, serum albumin level, and acceptable benefit-to-risk ratio (http://www.gntools.com). This tool provides an approach to the decision of prophylactic anticoagulation personalized to the individual’s needs and adaptable to dynamic changes in health status and risk profile. PMID:24336031

Electroconvulsive therapy and anticoagulation after pulmonary embolism: a case report

Directory of Open Access Journals (Sweden)

Julio Cesar Lazaro

2014-07-01

Full Text Available Introduction Electroconvulsive therapy (ECT is considered the most effective treatment for catatonia regardless its underlying condition. The rigid fixed posture and immobility observed in catatonia may lead to several clinical complications, of which, pulmonary embolism (PE is one of the most severe. The rapid improvement of the psychiatric condition in catatonia-related PE is essential, since immobility favors the occurrence of new thromboembolic events and further complications. In that scenario, ECT should be considered, based on a risk-benefit analysis, aiming at the faster resolution of the catatonia. Methods Case report and literature review. Results A 66-years-old woman admitted to the psychiatric ward with catatonia due to a depressive episode presented bilateral PE. Clinically stable, but still severely depressed after a trial of antidepressants, she was treated with ECT in the course of full anticoagulation with enoxaparin. After five ECT sessions, her mood was significantly better and she was walking and eating spontaneously. She did not present complications related either to PE or to anticoagulation. After the eighth ECT session, she evolved with hypomania, which was managed with oral medication adjustments. The patient was completely euthymic at discharge. Conclusion The case we presented provides further evidence to the anecdotal case reports on the safety of ECT in the course of concomitant full anticoagulant therapy after PE, and illustrates how, with the proper precautions, the benefits of ECT in such condition might outweigh its risks.

Effects of oversulfated and fucosylated chondroitin sulfates on coagulation. Challenges for the study of anticoagulant polysaccharides.

Science.gov (United States)

Fonseca, Roberto J C; Oliveira, Stephan-Nicollas M C G; Pomin, Vitor H; Mecawi, André S; Araujo, Iracema G; Mourão, Paulo A S

2010-05-01

We report the effects of a chemically oversulfated chondroitin sulfate and a naturally fucosylated chondroitin sulfate on the coagulation system. The former has been recently identified as a contaminant of heparin preparations and the latter has been proposed as an alternative anticoagulant. The mechanism of action of these polymers on coagulation is complex and target different components of the coagulation system. They have serpin-independent anticoagulant activity, which preponderates in plasma. They also have serpin-dependent anticoagulant activity but differ significantly in the target coagulation protease and preferential serpin. Their anticoagulant effects differ even more markedly when tested as inhibitors of coagulation proteases using plasma as a source of serpins. It is possible that the difference is due to the high availability of fucosylated chondroitin sulfate whereas oversulfated chondroitin sulfate has strong unspecific binding to plasma protein and low availability for the binding to serpins. When tested using a venous thrombosis experimental model, oversulfated chondroitin sulfate is less potent as an antithrombotic agent than fucosylated chondroitin sulfate. These highly sulfated chondroitin sulfates activate factor XII in in vitro assays, based on kallikrein release. However, only fucosylated chondroitin sulfate induces hypotension when intravenously injected into rats. In conclusion, the complexity of the regulatory mechanisms involved in the action of highly sulfated polysaccharides in coagulation requires their analysis by a combination of in vitro and in vivo assays. Our results are relevant due to the urgent need for new anticoagulant drugs or alternative sources of heparin.

Three-dimensionally Functionalized Reverse Phase Glycoprotein Array for Cancer Biomarker Discovery and Validation

OpenAIRE

Pan, Li; Aguilar, Hillary Andaluz; Wang, Linna; Iliuk, Anton; Tao, W. Andy

2016-01-01

Glycoproteins have vast structural diversity which plays an important role in many biological processes and have great potential as disease biomarkers. Here we report a novel functionalized reverse phase protein array (RPPA), termed polymer-based reverse phase GlycoProtein Array (polyGPA), to specifically capture and profile glycoproteomes, and validate glycoproteins. Nitrocellulose membrane functionalized with globular hydroxyaminodendrimers was used to covalently capture pre-oxidized glycan...

Determinants of the over-anticoagulation response during warfarin initiation therapy in Asian patients based on population pharmacokinetic-pharmacodynamic analyses.

Science.gov (United States)

Ohara, Minami; Takahashi, Harumi; Lee, Ming Ta Michael; Wen, Ming-Shien; Lee, Tsong-Hai; Chuang, Hui-Ping; Luo, Chen-Hui; Arima, Aki; Onozuka, Akiko; Nagai, Rui; Shiomi, Mari; Mihara, Kiyoshi; Morita, Takashi; Chen, Yuan-Tsong

2014-01-01

To clarify pharmacokinetic-pharmacodynamic (PK-PD) factors associated with the over-anticoagulation response in Asians during warfarin induction therapy, population PK-PD analyses were conducted in an attempt to predict the time-courses of the plasma S-warfarin concentration, Cp(S), and coagulation and anti-coagulation (INR) responses. In 99 Chinese patients we analyzed the relationships between dose and Cp(S) to estimate the clearance of S-warfarin, CL(S), and that between Cp(S) and the normal prothrombin concentration (NPT) as a coagulation marker for estimation of IC50. We also analyzed the non-linear relationship between NPT inhibition and the increase in INR to derive the non-linear index λ. Population analyses accurately predicted the time-courses of Cp(S), NPT and INR. Multivariate analysis showed that CYP2C9*3 mutation and body surface area were predictors of CL(S), that VKORC1 and CYP4F2 polymorphisms were predictors of IC50, and that baseline NPT was a predictor of λ. CL(S) and λ were significantly lower in patients with INR≥4 than in those with INR<4 (190 mL/h vs 265 mL/h, P<0.01 and 3.2 vs 3.7, P<0.01, respectively). Finally, logistic regression analysis revealed that CL(S), ALT and hypertension contributed significantly to INR≥4. All these results indicate that factors associated with the reduced metabolic activity of warfarin represented by CL(S), might be critical determinants of the over-anticoagulation response during warfarin initiation in Asians. ClinicalTrials.gov NCT02065388.

Determinants of the over-anticoagulation response during warfarin initiation therapy in Asian patients based on population pharmacokinetic-pharmacodynamic analyses.

Directory of Open Access Journals (Sweden)

Minami Ohara

Full Text Available To clarify pharmacokinetic-pharmacodynamic (PK-PD factors associated with the over-anticoagulation response in Asians during warfarin induction therapy, population PK-PD analyses were conducted in an attempt to predict the time-courses of the plasma S-warfarin concentration, Cp(S, and coagulation and anti-coagulation (INR responses. In 99 Chinese patients we analyzed the relationships between dose and Cp(S to estimate the clearance of S-warfarin, CL(S, and that between Cp(S and the normal prothrombin concentration (NPT as a coagulation marker for estimation of IC50. We also analyzed the non-linear relationship between NPT inhibition and the increase in INR to derive the non-linear index λ. Population analyses accurately predicted the time-courses of Cp(S, NPT and INR. Multivariate analysis showed that CYP2C9*3 mutation and body surface area were predictors of CL(S, that VKORC1 and CYP4F2 polymorphisms were predictors of IC50, and that baseline NPT was a predictor of λ. CL(S and λ were significantly lower in patients with INR≥4 than in those with INR<4 (190 mL/h vs 265 mL/h, P<0.01 and 3.2 vs 3.7, P<0.01, respectively. Finally, logistic regression analysis revealed that CL(S, ALT and hypertension contributed significantly to INR≥4. All these results indicate that factors associated with the reduced metabolic activity of warfarin represented by CL(S, might be critical determinants of the over-anticoagulation response during warfarin initiation in Asians.ClinicalTrials.gov NCT02065388.

A Carbohydrate Moiety of Secreted Stage-Specific Glycoprotein 4 Participates in Host Cell Invasion by Trypanosoma cruzi Extracellular Amastigotes

Science.gov (United States)

Florentino, Pilar T. V.; Real, Fernando; Orikaza, Cristina M.; da Cunha, Julia P. C.; Vitorino, Francisca N. L.; Cordero, Esteban M.; Sobreira, Tiago J. P.; Mortara, Renato A.

2018-01-01

Trypanosoma cruzi is the etiologic agent of Chagas’ disease. It is known that amastigotes derived from trypomastigotes in the extracellular milieu are infective in vitro and in vivo. Extracellular amastigotes (EAs) have a stage-specific surface antigen called Ssp-4, a GPI-anchored glycoprotein that is secreted by the parasites. By immunoprecipitation with the Ssp-4-specific monoclonal antibodies (mAb) 2C2 and 1D9, we isolated the glycoprotein from EAs. By mass spectrometry, we identified the core protein of Ssp-4 and evaluated mRNA expression and the presence of Ssp-4 carbohydrate epitopes recognized by mAb1D9. We demonstrated that the carbohydrate epitope recognized by mAb1D9 could promote host cell invasion by EAs. Although infectious EAs express lower amounts of Ssp-4 compared with less-infectious EAs (at the mRNA and protein levels), it is the glycosylation of Ssp-4 (identified by mAb1D9 staining only in infectious strains and recognized by galectin-3 on host cells) that is the determinant of EA invasion of host cells. Furthermore, Ssp-4 is secreted by EAs, either free or associated with parasite vesicles, and can participate in host-cell interactions. The results presented here describe the possible role of a carbohydrate moiety of T. cruzi surface glycoproteins in host cell invasion by EA forms, highlighting the potential of these moieties as therapeutic and vaccine targets for the treatment of Chagas’ disease. PMID:29692765

Anticoagulant drugs increase natural killer cell activity in lung cancer

Czech Academy of Sciences Publication Activity Database

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

2005-01-01

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

Self-monitoring and self-management of oral anticoagulation.

Science.gov (United States)

Heneghan, Carl J; Garcia-Alamino, Josep M; Spencer, Elizabeth A; Ward, Alison M; Perera, Rafael; Bankhead, Clare; Alonso-Coello, Pablo; Fitzmaurice, David; Mahtani, Kamal R; Onakpoya, Igho J

2016-07-05

The introduction of point-of-care devices for the management of patients on oral anticoagulation allows self-testing by the patient at home. Patients who self-test can either adjust their medication according to a pre-determined dose-INR (international normalized ratio) schedule (self-management), or they can call a clinic to be told the appropriate dose adjustment (self-monitoring). Increasing evidence suggests self-testing of oral anticoagulant therapy is equal to or better than standard monitoring. This is an updated version of the original review published in 2010. To evaluate the effects on thrombotic events, major haemorrhages, and all-cause mortality of self-monitoring or self-management of oral anticoagulant therapy compared to standard monitoring. For this review update, we re-ran the searches of the Cochrane Central Register of Controlled Trials (CENTRAL), 2015, Issue 6, the Cochrane Library, MEDLINE (Ovid, 1946 to June week 4 2015), Embase (Ovid, 1980 to 2015 week 27) on 1 July 2015. We checked bibliographies and contacted manufacturers and authors of relevant studies. We did not apply any language restrictions . Outcomes analysed were thromboembolic events, mortality, major haemorrhage, minor haemorrhage, tests in therapeutic range, frequency of testing, and feasibility of self-monitoring and self-management. Review authors independently extracted data and we used a fixed-effect model with the Mantzel-Haenzel method to calculate the pooled risk ratio (RR) and Peto's method to verify the results for uncommon outcomes. We examined heterogeneity amongst studies with the Chi(2) and I(2) statistics and used GRADE methodology to assess the quality of evidence. We identified 28 randomised trials including 8950 participants (newly incorporated in this update: 10 trials including 4227 participants). The overall quality of the evidence was generally low to moderate. Pooled estimates showed a reduction in thromboembolic events (RR 0.58, 95% CI 0.45 to 0

Filamentous fungi as production organisms for glycoproteins of bio-medical interest

NARCIS (Netherlands)

Maras, M.; Die, I. van; Contreras, R.; Hondel, C.A.M.J.J. van den

1999-01-01

Filamentous fungi are commonly used in the fermentation industry for large scale production of glycoproteins. Several of these proteins can be produced in concentrations up to 20-40 g per litre. The production of heterologous glycoproteins is at least one or two orders of magnitude lower but

Congenital Malformations Associated with the Administration of Oral Anticoagulants During Pregnancy

Science.gov (United States)

Pettifor, J. M.; Benson, R.

1975-01-01

Reported are case histories of three infants with congenital malformations (including defective formation of the nose and hands) associated with ingestion of oral anticoagulants during the first trimester of pregnancy. (CL)

Utilization of Oral Anticoagulation in a Teaching Hospital in Nigeria

African Journals Online (AJOL)

optimal antithrombotic effect. The oral drugs ... vitamin K-dependent clotting factors, which include factors. II, VII, IX, and X, ... hyperthyroidism) and those that decrease INR (pharmacokinetic: Barbiturates ... of anticoagulation, drug dosing, treatment outcome and .... national guidelines, and performance on quality measures.

Genomic clone encoding the α chain of the OKM1, LFA-1, and platelet glycoprotein IIb-IIIa molecules

International Nuclear Information System (INIS)

Cosgrove, L.J.; Sandrin, M.S.; Rajasekariah, P.; McKenzie, I.F.C.

1986-01-01

LFA-1, an antigen involved in cytolytic T lymphocyte-mediated killing, and Mac-1, the receptor for complement component C3bi, constitute a family of structurally and functionally related cell surface glycoproteins involved in cellular interactions. In both mouse and man, Mac-1 (OKM1) and LFA-1 share a common 95-kDa β subunit but are distinguished by their α chains, which have different cellular distributions, apparent molecular masses (165 and 177 kDa, respectively), and peptide maps. The authors report the isolation of a genomic clone from a human genomic library that on transfection into mouse fibroblasts produced a molecule(s) reactive with monoclonal antibodies to OKM1, to LFA-1, and to platelet glycoprotein IIb-IIIa. This gene was cloned by several cycles of transfection of L cells with a human genomic library cloned in λ phase Charon 4A and subsequent rescue of the λ phage. Transfection with the purified recombinant λ DNA yielded a transfectant that expressed the three human α chains of OKM1, LFA-1, and glycoprotein IIb-IIIa, presumably in association with the murine β chain

Co-treatment by docetaxel and vinblastine breaks down P-glycoprotein mediated chemo-resistance

Directory of Open Access Journals (Sweden)

Mahsa Mohseni

2016-03-01

Results: Combination treatment of the cells with docetaxel and vinblastine decreased the IC50 values for docetaxel from (30±3.1 to (15±2.6 nM and for vinblastine from (30±5.9 to (5±5.6 nM (P≤0.05.               P-glycoprotein mRNA expression level showed a significant up-regulation in the cells incubated with each drug alone (P≤0.001. Incubation of the cells with combined concentrations of both agents neutralized P-glycoprotein overexpression (P≤0.05. Adding verapamil, a P-glycoprotein inhibitor caused a further increase in the percentage of apoptotic cells when the cells were treated with both agents.  Conclusion:Our results suggest that combination therapy along with P-glycoprotein inhibition can be considered as a novel approach to improve the efficacy of chemotherapeutics in cancer patients with high P-glycoprotein expression.

Upsetting the apple cart: a community anticoagulation clinic survey of life event factors that undermine safe therapy.

Science.gov (United States)

Edmundson, Sarah; Stuenkel, Diane L; Connolly, Phyllis M

2005-09-01

Anticoagulation therapy is a life-enhancing therapy for patients who are at risk for embolic events secondary to atrial fibrillation, valve replacement, and other comorbidities. Clinicians are motivated to decrease the amount of time that patients are either under- or over-anticoagulated, common conditions that decrease patient safety at either extreme. The primary purpose of this descriptive study was to examine the relationship between personal life event factors as measured by Norbeck's Life Events Questionnaire, core demographics such as age and income, and anticoagulation regulation. Although many factors affect anticoagulation therapy, the precise impact of life events, positive or negative, is unknown. The salient findings of this study (n = 202) showed a small, though statistically significant, inverse relationship (r = -0.184, P < .01) between negative life events and decreased time within therapeutic international normalized ratio. Total Life Event scores showed a statistically significant inverse relationship (r = -0.159, P < .05) to international normalized ratio time within therapeutic level. Lower income was inversely associated with higher negative Life Event scores (r = -0.192, P < .01). The findings demonstrate the need for strategies that address the potential impact of life events in conjunction with coexisting screening measures used in anticoagulation clinics. Implications for this study are limited by lack of methodology documenting concurrent social support factors and limitations of the research tool to reflect life event issues specific to outpatient seniors.

Current practice of antiplatelet and anticoagulation management in post-cardiac surgery patients: a national audit.

Science.gov (United States)

Hosmane, Sharath; Birla, Rashmi; Marchbank, Adrian

2012-04-01

The Audit and Guidelines Committee of the European Association for Cardio-Thoracic Surgery recently published a guideline on antiplatelet and anticoagulation management in cardiac surgery. We aimed to assess the awareness of the current guideline and adherence to it in the National Health Service through this National Audit. We designed a questionnaire consisting of nine questions covering various aspects of antiplatelet and anticoagulation management in post-cardiac surgery patients. A telephonic survey of the on-call cardiothoracic registrars in all the cardiothoracic centres across the UK was performed. All 37 National Health Service hospitals in the UK with 242 consultants providing adult cardiac surgical service were contacted. Twenty (54%) hospitals had a unit protocol for antiplatelet and anticoagulation management in post-cardiac surgery. Only 23 (62.2%) registrars were aware of current European Association for Cardio-Thoracic Surgery guidelines. Antiplatelet therapy is variable in the cardiac surgical units across the country. Low-dose aspirin is commonly used despite the recommendation of 150-300 mg. The loading dose of aspirin within 24 h as recommended by the guideline is followed only by 60.7% of surgeons. There was not much deviation from the guideline with respect to the anticoagulation therapy.

Purification, structural characterization and anticoagulant properties of fucosylated chondroitin sulfate isolated from Holothuria mexicana.

Science.gov (United States)

Mou, Jiaojiao; Wang, Cong; Li, Wenjing; Yang, Jie

2017-05-01

A novel fucosylated chondroitin sulfate (HmG) was isolated from sea cucumber Holothuria mexicana, the structure of which was characterized by monosaccharide composition, disaccharide composition, IR, 1 H and 13 C NMR spectrum, additionally with two dimensional NMR spectrum of degraded HmG (DHmG). The backbone of HmG was identified as chondroitin 6-O sulfate, while the major O-4 sulfated fucose branches linked to O-3 position of glucuronic acid in almost every disaccharide unit. The anticoagulant activities of HmG and DHmG were assessed and compared with heparin and low molecular weight heparin. The results indicated that HmG and DHmG both could significantly prolong the activated partial thrombo-plastin time, and the properties were well related to its molecular weight. DHmG showed similar anticoagulant properties to low molecular weight heparin with less bleeding risks, making it a safer anticoagulant drug. Copyright © 2017 Elsevier B.V. All rights reserved.

Educational Level, Anticoagulation Quality, and Clinical Outcomes in Elderly Patients with Acute Venous Thromboembolism: A Prospective Cohort Study.

Science.gov (United States)

Hofmann, Eveline; Faller, Nicolas; Limacher, Andreas; Méan, Marie; Tritschler, Tobias; Rodondi, Nicolas; Aujesky, Drahomir

2016-01-01

Whether the level of education is associated with anticoagulation quality and clinical outcomes in patients with acute venous thromboembolism (VTE) is uncertain. We thus aimed to investigate the association between educational level and anticoagulation quality and clinical outcomes in elderly patients with acute VTE. We studied 817 patients aged ≥65 years with acute VTE from a Swiss prospective multicenter cohort study (09/2009-12/2013). We defined three educational levels: 1) less than high school, 2) high school, and 3) post-secondary degree. The primary outcome was the anticoagulation quality, expressed as the percentage of time spent in the therapeutic INR range (TTR). Secondary outcomes were the time to a first recurrent VTE and major bleeding. We adjusted for potential confounders and periods of anticoagulation. Overall, 56% of patients had less than high school, 25% a high school degree, and 18% a post-secondary degree. The mean percentage of TTR was similar across educational levels (less than high school, 61%; high school, 64%; and post-secondary, 63%; P = 0.36). Within three years of follow-up, patients with less than high school, high school, and a post-secondary degree had a cumulative incidence of recurrent VTE of 14.2%, 12.9%, and 16.4%, and a cumulative incidence of major bleeding of 13.3%, 15.1%, and 15.4%, respectively. After adjustment, educational level was neither associated with anticoagulation quality nor with recurrent VTE or major bleeding. In elderly patients with VTE, we did not find an association between educational level and anticoagulation quality or clinical outcomes.

Cost evaluation of two methods of post tooth extraction hemostasis in patients on anticoagulant therapy.

Science.gov (United States)

Zusman, S P; Lustig, J P; Bin Nun, G

1993-06-01

The classical management of patients on oral anticoagulant therapy included hospitalisation, cessation of the anticoagulant agent, and extraction of teeth when the prothrombine levels rise. This method was substituted in the High Risk Dental Clinic at Barzilai Medical Center in Ashkelon by use of a tissue sealant (Tisseel) which does not need hospitalisation nor cessation of the anticoagulant therapy. In comparing the last 23 sessions employing the former method to the first 23 sessions using the new method there were significant differences in the cost effectiveness for the health system, provider, insurer and patient. Despite the fact that from the health system point of view the new method is much more cost effective, there is no financial incentive for the provider (hospital) nor awareness on the part of the insurer (General Sick Fund) to embrace it and 'market' it.

Sulfated polysaccharides with antioxidant and anticoagulant activity from the sea cucumber Holothuria fuscogliva

Science.gov (United States)

Li, Rongfeng; Yu, Huahua; Yue, Yang; Liu, Song; Xing, Rong'e.; Chen, Xiaolin; Li, Pengcheng

2017-07-01

Sea cucumber is a traditional nutritional food and medicinal resource with many bioactive components in China. Holothuria fuscogliva is a big sea cucumber with a rich of bioactive polysaccharides. To investigate the bioactivities of the polysaccharides from sea cucumber H. fuscogliva, we prepared the sulfated polysaccharides (HfP) from sea cucumber H. fuscogliva using a protease hydrolysis method. Antioxidant activities of HfP were investigated, including hydroxyl radical scavenging activity and superoxide radical scavenging activity. And, the anticoagulant activities of HfP were studied, including the activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT). The average molecular weight was 1 867.1 Da, with a sulfate content of 20.7%. In addition, the molar ratio of monosaccharide composition of HfP was Man: Rha: Glc A: Glc: Gal: Xyl: Fuc=0.083 6: 0.437: 0.134: 0:1.182: 0.748: 1. It had a strong antioxidant activity, the hydroxyl and superoxide radical scavenging activity EC50 of HfP was 3.74 and 0.037 mg/mL, respectively. It also showed a good anticoagulant activity in our study. The APTT of HfP was much higher than that of heparin sodium, and the PT and TT of HfP was close to that of heparin sodium at a low concentration. Therefore, HfP shows a good antioxidant and anticoagulant activity and it may become a potential candidate of the natural antioxidant and anticoagulant and will have a good application future in health product or medicine industry.

Effects of chronic ethanol administration on hepatic glycoprotein secretion in the rat

International Nuclear Information System (INIS)

Sorrell, M.F.; Nauss, J.M.; Donohue, T.M. Jr.; Tuma, D.J.

1983-01-01

The effects of chronic ethanol feeding on protein and glycoprotein synthesis and secretion were studied in rat liver slices. Liver slices from rats fed ethanol for 4-5 wk showed a decreased ability to incorporate [ 14 C]glucosamine into medium trichloracetic acid-precipitable proteins when compared to the pair-fed controls; however, the labeling of hepatocellular glycoproteins was unaffected by chronic ethanol treatment. Immunoprecipitation of radiolabeled secretory (serum) glycoproteins with antiserum against rat serum proteins showed a similar marked inhibition in the appearance of glucosamine-labeled proteins in the medium of slices from ethanol-fed rats. Minimal effects, however, were noted in the labeling of intracellular secretory glycoproteins. Protein synthesis, as determined by measuring [ 14 C]leucine incorporation into medium and liver proteins, was decreased in liver slices from ethanol-fed rats as compared to the pair-fed controls. This was the case for both total proteins as well as immunoprecipitable secretory proteins, although the labeling of secretory proteins retained in the liver slices was reduced to a lesser extent than total radiolabeled hepatic proteins. When the terminal sugar, [ 14 C]fucose, was employed as a precursor in order to more closely focus on the final steps of hepatic glycoprotein secretion, liver slices obtained from chronic ethanol-fed rats exhibited impaired secretion of fucose-labeled proteins into the medium. When ethanol (5 or 10 mM) was added to the incubation medium containing liver slices from the ethanol-fed rats, the alterations in protein and glycoprotein synthesis and secretion caused by the chronic ethanol treatment were further potentiated. The results of this study indicate that liver slices prepared from chronic ethanol-fed rats exhibit both impaired synthesis and secretion of proteins and glycoproteins, and these defects are further potentiated by acute ethanol administration

Identification, isolation, and N-terminal sequencing of style glycoproteins associated with self-incompatibility in Nicotiana alata.

Science.gov (United States)

Jahnen, W; Batterham, M P; Clarke, A E; Moritz, R L; Simpson, R J

1989-05-01

S-Gene-associated glycoproteins (S-glycoproteins) from styles of Nicotiana alata, identified by non-equilibrium two-dimensional electrophoresis, were purified by cation exchange fast protein liquid chromatography with yields of 0.5 to 8 micrograms of protein per style, depending on the S-genotype of the plant. The method relies on the highly basic nature of the S-glycoproteins. The elution profiles of the different S-glycoproteins from the fast protein liquid chromatography column were characteristic of each S-glycoprotein, and could be used to establish the S-genotype of plants in outbreeding populations. In all cases, the S-genotype predicted from the style protein profile corresponded to that predicted from DNA gel blot analysis using S-allele-specific DNA probes and to that established by conventional breeding tests. Amino-terminal sequences of five purified S-glycoproteins showed a high degree of homology with the previously published sequences of N. alata and Lycopersicon esculentum S-glycoproteins.

Anticoagulant Prairie Dog Bait Risk Mitigation Measures to Protect Endangered Species

Science.gov (United States)

This Web page contains information on how certified pesticide applicators can use anticoagulant prairie dog bait products such as Rozol and Kaput-D while minimizing exposure risks to listed and non-target species.

Use of Non-Vitamin K Antagonist Oral Anticoagulants 2008-2016

DEFF Research Database (Denmark)

Haastrup, Simone; Hellfritzsch, Maja; Rasmussen, Lotte

2018-01-01

We aimed to provide detailed utilization data on the total use of non-vitamin K antagonist oral anticoagulants (NOACs) since their introduction in 2008. Using the nationwide Danish National Prescription Registry, we identified all individuals filling prescriptions for NOACs 2008-2016. We reported...

Stratifying the risks of oral anticoagulation in patients with liver disease.

Science.gov (United States)

Efird, Lydia M; Mishkin, Daniel S; Berlowitz, Dan R; Ash, Arlene S; Hylek, Elaine M; Ozonoff, Al; Reisman, Joel I; Zhao, Shibei; Jasuja, Guneet K; Rose, Adam J

2014-05-01

Chronic liver disease presents a relative contraindication to warfarin therapy, but some patients with liver disease nevertheless require long-term anticoagulation. The goal is to identify which patients with liver disease might safely receive warfarin. Among 102 134 patients who received warfarin from the Veterans Affairs from 2007 to 2008, International Classification of Diseases-Ninth Revision codes identified 1763 patients with chronic liver disease. Specific diagnoses and laboratory values (albumin, aspartate aminotransferase, alanine aminotransferase, creatinine, and cholesterol) were examined to identify risk of adverse outcomes, while controlling for available bleeding risk factors. Outcomes included percent time in therapeutic range, a measure of anticoagulation control, and major hemorrhagic events, by International Classification of Diseases-Ninth Revision codes. Patients with liver disease had lower mean time in therapeutic range (53.5%) when compared with patients without (61.7%; P<0.001) and more hemorrhages (hazard ratio, 2.02; P<0.001). Among patients with liver disease, serum albumin and creatinine levels were the strongest predictors of both outcomes. We created a 4-point score system: patients received 1 point each for albumin (2.5-3.49 g/dL) or creatinine (1.01-1.99 mg/dL), and 2 points each for albumin (<2.5 g/dL) or creatinine (≥2 mg/dL). This score predicted both anticoagulation control and hemorrhage. When compared with patients without liver disease, those with a score of zero had modestly lower time in therapeutic range (56.7%) and no increase in hemorrhages (hazard ratio, 1.16; P=0.59), whereas those with the worst score (4) had poor control (29.4%) and high hazard of hemorrhage (hazard ratio, 8.53; P<0.001). Patients with liver disease receiving warfarin have poorer anticoagulation control and more hemorrhages. A simple 4-point scoring system using albumin and creatinine identifies those at risk for poor outcomes. © 2014 American

A Novel Method for Detection of Glycoproteins on Sodium Dodecyl Sulphate Polyacrylamide Gel Using Radio-Iodinated Tyrosine

DEFF Research Database (Denmark)

Nalla, Amarnadh; Draz, Hossam M.; Dole, Anita

2009-01-01

The aim of this study is to develop a novel method for detection of glycoproteins on polyacrylamide gel. In this method, radio-iodinated-tyrosine (125I-tyrosine) was conjugated to glycoprotein by schiff's base mechanism on the sodium dodecyl sulfate- polyacrylamide gel. Ovalbumin and Concanavalin...... of glycoproteins using 125I-tyrosine selectively detected ovalbumin. Present results showed that MPD enhanced glycoprotein detection method can be used as a sensitive tool for the detection of glycoproteins on polyacrylamide gel...

The recent clinical trials on use of the novel direct oral anticoagulants in patients with venous thromboembolism: a review

Directory of Open Access Journals (Sweden)

Gualtiero Palareti

2014-10-01

Full Text Available Venous thromboembolism (VTE, encompassing deep vein thrombosis and pulmonary embolism, requires an immediate anticoagulation, that has been carried out so far by administering a parenteral anticoagulant drug (heparin or derivatives overlapped with an oral vitamin K antagonist (VKA, more often warfarin. Several new direct oral anticoagulants (DOACs, with a mechanism of action completely different than VKA, have been developed in recent years. Recent clinical trials have investigated their use in VTE patients showing results at least equal for efficacy and safety, and sometime even better, as the standard anticoagulant treatment. There are differences in the design of the trials. In two cases the involved DOAC was administered immediately after VTE diagnosis as a single drug treatment (rivaroxaban and apixaban, whereas in the other trials (involving dabigatran and edoxaban the DOAC was administered after an initial course of approximately 7 days with heparin or derivatives. Some clinical trials have also investigated the use of DOACs for extended anticoagulant treatment after the acute phase. Aim of this article is to review the results of the currently available clinical trials that have compared the use of DOACs versus the standard of care in patients with VTE.

Spatial Localization of the Ebola Virus Glycoprotein Mucin-Like Domain Determined by Cryo-Electron Tomography

OpenAIRE

Tran, Erin E. H.; Simmons, James A.; Bartesaghi, Alberto; Shoemaker, Charles J.; Nelson, Elizabeth; White, Judith M.; Subramaniam, Sriram

2014-01-01

The Ebola virus glycoprotein mucin-like domain (MLD) is implicated in Ebola virus cell entry and immune evasion. Using cryo-electron tomography of Ebola virus-like particles, we determined a three-dimensional structure for the full-length glycoprotein in a near-native state and compared it to that of a glycoprotein lacking the MLD. Our results, which show that the MLD is located at the apex and the sides of each glycoprotein monomer, provide a structural template for analysis of MLD function.

P-glycoprotein targeted nanoscale drug carriers

KAUST Repository

Li, Wengang; Abu Samra, Dina Bashir Kamil; Merzaban, Jasmeen; Khashab, Niveen M.

2013-01-01

Multi-drug resistance (MDR) is a trend whereby tumor cells exposed to one cytotoxic agent develop cross-resistance to a range of structurally and functionally unrelated compounds. P -glycoprotein (P -gp) efflux pump is one of the mostly studied drug

Computational identification of epitopes in the glycoproteins of novel bunyavirus (SFTS virus) recognized by a human monoclonal antibody (MAb 4-5)

Science.gov (United States)

Zhang, Wenshuai; Zeng, Xiaoyan; Zhang, Li; Peng, Haiyan; Jiao, Yongjun; Zeng, Jun; Treutlein, Herbert R.

2013-06-01

In this work, we have developed a new approach to predict the epitopes of antigens that are recognized by a specific antibody. Our method is based on the "multiple copy simultaneous search" (MCSS) approach which identifies optimal locations of small chemical functional groups on the surfaces of the antibody, and identifying sequence patterns of peptides that can bind to the surface of the antibody. The identified sequence patterns are then used to search the amino-acid sequence of the antigen protein. The approach was validated by reproducing the binding epitope of HIV gp120 envelop glycoprotein for the human neutralizing antibody as revealed in the available crystal structure. Our method was then applied to predict the epitopes of two glycoproteins of a newly discovered bunyavirus recognized by an antibody named MAb 4-5. These predicted epitopes can be verified by experimental methods. We also discuss the involvement of different amino acids in the antigen-antibody recognition based on the distributions of MCSS minima of different functional groups.

Na2EDTA anticoagulant impaired blood samples from the teleost Piaractus mesopotamicus

Directory of Open Access Journals (Sweden)

Thaís Heloisa Vaz Farias

2016-05-01

Full Text Available Abstract: The present study aimed to evaluate the effects of Na heparin and Na2EDTA on blood of Piaractus mesopotamicus (360.7±42.4g, 26.4±1.0cm. Twenty fishes were sampled in two experiment trials, ten for erythrocyte fragility analysis and ten for hematologic and plasma biochemical study. The blood collected by venous-caudal puncture was fractioned and stored in anticoagulants solution: Na2EDTA 10%, Na2EDTA 3%, Na heparin 5000 IU and Na heparin 100 IU. Plasmatic levels of calcium presented in the Na2EDTA stored samples were about 80% lower than both heparin groups. Blood samples of P. mesopotamicus stored with Na2EDTA demonstrated increase in the hematocrit and MCV, and decrease in MCHC. The dose-response effect was observed in this study. The results are reinforced by the higher levels of plasmatic protein and hemolysis presented in the Na2EDTA 10% stored blood, confirming the deleterious effect of this anticoagulant treatment on the quality of blood samples. Na2EDTA is not indicated to store P. mesopotamicus blood samples, but sodium heparin at 100 IU is the most recommended anticoagulant, since this treatment presented the lower rate of alterations in the stored blood.

[Pathogenesis and Laboratory Findings in Antiphospholipid Syndrome, Especially Associated with Lupus Anticoagulant].

Science.gov (United States)

Ieko, Masahiro; Naito, Sumiyoshi; Yoshida, Mika; Takahashi, Nobuhiko

2015-10-01

Antiphospholipid syndrome (APS), an acquired thrombotic condition, is a complex clinical state characterized by the presence of circulating antiphospholipid antibodies in patients with thrombosis or pregnancy morbidity. Revised APS classification criteria are used for diagnosis, which include at least one clinical criterion (thrombosis or pregnancy loss) and at least one of the laboratory criteria [anticardiolipin antibodies, anti-β2GPI antibodies, lupus anticoagulant (LA)]. LA is also an independent risk factor for developing thrombosis, though some LA-positive cases have been reported to have a bleeding symptom. Lupus anticoagulant-hypoprothrombinemia syndrome (LAHPS) is a rare disorder characterized by a bleeding tendency due to low prothrombin activity in patients with LA, and has recently been reported not only in children but also in adults We have encountered LA cases with bleeding and low coagulation factor activities except for prothrombin. Based on our findings, we propose that LA-positive cases with a bleeding symptom and characterized by low coagulation factor activity including prothrombin be termed lupus anticoagulant-associated coagulopathy (LAAC). Furthermore, coagulation factor autoantibodies are often detected in LAAC patients; thus, correct measurement of LA is important to distinguish LAAC patients from those possessing an inhibitor to coagulation factors such as acquired hemophilia A as well as to select the optimal therapeutic strategy.

Practice points in gynecardiology: Abnormal uterine bleeding in premenopausal women taking oral anticoagulant or antiplatelet therapy.

Science.gov (United States)

Maas, Angela H E M; Euler, Mia von; Bongers, Marlies Y; Rolden, Herbert J A; Grutters, Janneke P C; Ulrich, Lian; Schenck-Gustafsson, Karin

2015-12-01

A growing number of premenopausal women are currently using antithrombotic and/or (dual) antiplatelet therapy for various cardiovascular indications. These may induce or exacerbate abnormal uterine bleeding and more awareness and knowledge among prescribers is required. Heavy and irregular menstrual bleeding is common in women in their forties and may have a variety of underlying causes that require different treatment options. Thus using anticoagulants in premenopausal women demands specific expertise and close collaboration between cardiovascular physicians and gynecologists. In this article we summarize the scope of the problem and provide practical recommendations for the care for young women taking anticoagulants and/or (dual) antiplatelet therapy. We also recommend that more safety data on uterine bleeding with novel anticoagulants in premenopausal women should be obtained. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Management of anticoagulation in hip fractures: A pragmatic approach.

Science.gov (United States)

Yassa, Rafik; Khalfaoui, Mahdi Yacine; Hujazi, Ihab; Sevenoaks, Hannah; Dunkow, Paul

2017-09-01

Hip fractures are common and increasing with an ageing population. In the United Kingdom, the national guidelines recommend operative intervention within 36 hours of diagnosis. However, long-term anticoagulant treatment is frequently encountered in these patients which can delay surgical intervention. Despite this, there are no set national standards for management of drug-induced coagulopathy pre-operatively in the context of hip fractures.The aim of this study was to evaluate the management protocols available in the current literature for the commonly encountered coagulopathy-inducing agents.We reviewed the current literature, identified the reversal agents used in coagulopathy management and assessed the evidence to determine the optimal timing, doses and routes of administration.Warfarin and other vitamin K antagonists (VKA) can be reversed effectively using vitamin K with a dose in the range of 2 mg to 10 mg intravenously to correct coagulopathy.The role of fresh frozen plasma is not clear from the current evidence while prothrombin complex remains a reliable and safe method for immediate reversal of VKA-induced coagulopathy in hip fracture surgery or failed vitamin K treatment reversal.The literature suggests that surgery should not be delayed in patients on classical antiplatelet medications (aspirin or clopidogrel), but spinal or regional anaesthetic methods should be avoided for the latter. However, evidence regarding the use of more novel antiplatelet medications (e.g. ticagrelor) and direct oral anticoagulants remains a largely unexplored area in the context of hip fracture surgery. We suggest treatment protocols based on best available evidence and guidance from allied specialties.Hip fracture surgery presents a common management dilemma where semi-urgent surgery is required. In this article, we advocate an evidence-based algorithm as a guide for managing these anticoagulated patients. Cite this article: EFORT Open Rev 2017;2:394-402. DOI: 10.1302/2058-5241.2.160083.

Concurrent use of tramadol and oral vitamin K antagonists and the risk of excessive anticoagulation

DEFF Research Database (Denmark)

Pottegård, Anton; Meegaard, P. M.; Holck, L. H.

2013-01-01

.9-5.2). This corresponds to, on average, one excess case per 250 treatment years (CI 125-584). The result is potentially confounded by concomitant paracetamol use and the presence of acute illness. CONCLUSION: Caution is advised when using tramadol in patients using VKA, and if possible, an alternative pain......OBJECTIVES: The objective was to assess whether the concurrent use of tramadol and vitamin K antagonists (VKAs) leads to an increased risk of excessive anticoagulation. DESIGN: The study was designed as a case-control study, nested within users of VKA and with tramadol use as our main exposure. We...... anticoagulation attributable to the use of tramadol. RESULTS: A total of 178 patients were included, 30 of which were exposed to tramadol, along with 2643 controls, 114 of which were exposed to tramadol. The adjusted odds-ratio for experiencing excessive anticoagulation during use of tramadol was 3.1 (1...

Real-life Use of Anticoagulants in Venous Thromboembolism With a Focus on Patients With Exclusion Criteria for Direct Oral Anticoagulants.

Science.gov (United States)

Moustafa, Farès; Pesavento, Raffaele; di Micco, Pierpaolo; González-Martínez, José; Quintavalla, Roberto; Peris, Maria-Luisa; Porras, José Antonio; Falvo, Nicolas; Baños, Pilar; Monreal, Manuel

2018-04-01

We assessed the real-life use of direct oral anticoagulants (DOACs) in patients with venous thromboembolism (VTE) and exclusion criteria for randomized trials. From 2013 to 2016, 3,578 of 18,853 patients (19%) had exclusion criteria. Irrespective of which anticoagulant was chosen, they had more VTE recurrences (hazard ratio (HR): 3.10; 95% confidence interval (CI): 2.47-3.88), major bleeds (HR: 4.10; 95% CI: 3.38-4.96), and deaths (HR: 9.47; 95% CI: 8.46-10.6) than those without exclusion criteria. During initial therapy, no patient with exclusion criteria on DOACs (n = 115) recurred, but those on rivaroxaban bled less often (adjusted HR: 0.18; 95% CI: 0.04-0.79) than those on unfractionated heparin (n = 224) and similar to those (n = 3,172) on low-molecular-weight (LMWH) heparin. For long-term therapy, patients on rivaroxaban (n = 151) had nonsignificantly fewer VTE recurrences (adjusted HR: 0.74; 95% CI: 0.08-1.32) and major bleeds (adjusted HR: 0.41; 95% CI: 0.15-1.15) than those on LMWH (n = 2,071). The efficacy and safety of DOACs were similar to standard therapy. © 2017 American Society for Clinical Pharmacology and Therapeutics.

Glycan shield and fusion activation of a deltacoronavirus spike glycoprotein fine-tuned for enteric infections.

Science.gov (United States)

Xiong, Xiaoli; Tortorici, M Alejandra; Snijder, Joost; Yoshioka, Craig; Walls, Alexandra C; Li, Wentao; McGuire, Andrew T; Rey, Félix A; Bosch, Berend-Jan; Veesler, David

2017-11-01

Coronaviruses recently emerged as major human pathogens causing outbreaks of severe acute respiratory syndrome and Middle-East respiratory syndrome. They utilize the spike (S) glycoprotein anchored in the viral envelope to mediate host attachment and fusion of the viral and cellular membranes to initiate infection. The S protein is a major determinant of the zoonotic potential of coronaviruses and is also the main target of the host humoral immune response. We report here the 3.5 Å resolution cryo-electron microscopy structure of the S glycoprotein trimer from the pathogenic porcine deltacoronavirus (PDCoV), which belongs to the recently identified delta genus. Structural and glycoproteomics data indicate that the glycans of PDCoV S are topologically conserved when compared with the human respiratory coronavirus HCoV-NL63 S, resulting in similar surface areas being shielded from neutralizing antibodies and implying that both viruses are under comparable immune pressure in their respective hosts. The structure further reveals a shortened S 2 ' activation loop, containing a reduced number of basic amino acids, which participates to rendering the spike largely protease-resistant. This property distinguishes PDCoV S from recently characterized betacoronavirus S proteins and suggests that the S protein of enterotropic PDCoV has evolved to tolerate the protease-rich environment of the small intestine and to fine-tune its fusion activation to avoid premature triggering and reduction of infectivity. IMPORTANCE Coronaviruses use transmembrane spike (S) glycoprotein trimers to promote host attachment and fusion of the viral and cellular membranes. We determined a near-atomic resolution cryo-electron microscopy structure of the S ectodomain trimer from the pathogenic porcine deltacoronavirus (PDCoV), which is responsible for diarrhea in piglets and has had devastating consequences for the swine industry worldwide. Structural and glycoproteomics data reveal that PDCoV S is

Anticoagulant use for the prevention of stroke in patients with atrial fibrillation: findings from a multi-payer analysis.

Science.gov (United States)

Lang, Kathleen; Bozkaya, Duygu; Patel, Aarti A; Macomson, Brian; Nelson, Winnie; Owens, Gary; Mody, Samir; Schein, Jeff; Menzin, Joseph

2014-07-28

Oral anticoagulation is recommended for stroke prevention in intermediate/high stroke risk atrial fibrillation (AF) patients. The objective of this study was to demonstrate the usefulness of analytic software tools for descriptive analyses of disease management in atrial AF; a secondary objective is to demonstrate patterns of potential anticoagulant undertreatment in AF. Retrospective data analyses were performed using the Anticoagulant Quality Improvement Analyzer (AQuIA), a software tool designed to analyze health plan data. Two-year data from five databases were analyzed: IMS LifeLink (IMS), MarketScan Commercial (MarketScanCommercial), MarketScan Medicare Supplemental (MarketScanMedicare), Clinformatics™ DataMart, a product of OptumInsight Life Sciences (Optum), and a Medicaid Database (Medicaid). Included patients were ≥ 18 years old with a new or existing diagnosis of AF. The first observed AF diagnosis constituted the index date, with patient outcomes assessed over a one year period. Key study measures included stroke risk level, anticoagulant use, and frequency of International Normalized Ratio (INR) monitoring. High stroke risk (CHADS2 ≥ 2 points) was estimated in 54% (IMS), 22% (MarketScanCommercial), 64% (MarketscanMedicare), 42% (Optum) and 62% (Medicaid) of the total eligible population. Overall, 35%, 29%, 38%, 39% and 16% of all AF patients received an anticoagulant medication in IMS, MarketScanCommercial, MarketScanMedicare, Optum and Medicaid, respectively. Among patients at high risk for stroke, 19% to 51% received any anticoagulant. The AQuIA provided a consistent platform for analysis across multiple AF populations with varying baseline characteristics. Analyzer results show that many high-risk AF patients in selected commercial, Medicare-eligible, and Medicaid populations do not receive appropriate thromboprophylaxis, as recommended by treatment guidelines.

Cross-cultural adaptation and psychometric properties of the Brazilian-Portuguese version of the Duke Anticoagulation Satisfaction Scale.

Science.gov (United States)

Pelegrino, Flávia M; Dantas, Rosana A S; Corbi, Inaiara S A; da Silva Carvalho, Ariana R; Schmidt, André; Pazin Filho, Antônio

2012-09-01

The aim of this study was to evaluate the internal reliability and validity of the Brazilian-Portuguese version of Duke Anticoagulation Satisfaction Scale (DASS) among cardiovascular patients. Oral anticoagulation is widely used to prevent and treat thromboembolic events in several conditions, especially in cardiovascular diseases; however, this therapy can induce dissatisfaction and reduce the quality of life. Methodological and cross-sectional research design. The cultural adaptation of the DASS included the translation and back-translation, discussions with healthcare professionals and patients to ensure conceptual equivalence, semantic evaluation and instrument pretest. The Brazilian-Portuguese version of the DASS was tested among subjects followed in a university hospital anticoagulation outpatient clinic. The psychometric properties were assessed by construct validity (convergent, known groups and dimensionality) and internal consistency/reliability (Cronbach's alpha). A total of 180 subjects under oral anticoagulation formed the baseline validation population. DASS total score and SF-36 domain correlations were moderate for General health (r=-0.47, pDASS score and most of the subscales, except Limitation (r=-0.375, pscale, and it ranged from 0.76 (hassles and burdens)-0.46 (psychological impact) among the domains, confirming the internal consistency reliability. The Brazilian-Portuguese version of the DASS has shown levels of reliability and validity comparable with the original English version. Healthcare practitioners and researchers need internationally validated measurement tools to compare outcomes of interventions in clinical management and research tools in oral anticoagulation therapy. © 2011 Blackwell Publishing Ltd.

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

LENUS (Irish Health Repository)

Preston, Roger J S

2012-02-01

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

Glycoproteins of axonal transport: affinity chromatography on fucose-specific lectins

Energy Technology Data Exchange (ETDEWEB)

Gustavsson, S.; Ohlson, C.; Karlsson, J.O.

1982-03-01

Rapidly transported fucose-labeled glycoproteins from axons of rabbit retinal ganglion cells were solubilized with nonionic detergents. The solubilized components were subjected to affinity chromatography on three different fucose-specific lectins. A recently characterized fucose-specific lectin from Aleuria aurantia bound reversibly approximately 60% of the applied protein-bound radioactivity. The lectins from Lotus tetragonolobus and Ulex europaeus bound are very small proportions of the labeled rapidly transported glycoproteins.

Anticoagulation: Where have we come from and where are we going ...

African Journals Online (AJOL)

is its predictable renal excretion, with low inter- and intra-individual variability.[11] Clinically, this ... recent meta-analysis of 50 000 patients requiring anticoagulation ... data supporting the use of NOACs in secondary stroke prevention in. NVAF.

Initiation of anticoagulation in atrial fibrillation

DEFF Research Database (Denmark)

Gundlund, A.; Staerk, L.; Fosbøl, E. L.

2017-01-01

Background: The use of non-vitamin K antagonist oral anticoagulants (NOACs) for stroke prophylaxis in atrial fibrillation (AF) is increasing rapidly. We compared characteristics of AF patients initiated on NOACs versus vitamin K antagonists (VKAs). Methods: Using Danish nationwide registry data, we...... compared with a VKA [odds ratio (OR) 1.35, 95% confidence interval (CI) 1.28–1.43]. By contrast, patients with a history of myocardial infarction were less likely to be initiated on a NOAC compared with a VKA (OR 0.72, 95% CI 0.67–0.77). Conclusions: Atrial fibrillation patients who were initiated...

Impact of anticoagulation therapy on valve haemodynamic deterioration following transcatheter aortic valve replacement.

Science.gov (United States)

Del Trigo, María; Muñoz-García, Antonio J; Latib, Azeem; Auffret, Vincent; Wijeysundera, Harindra C; Nombela-Franco, Luis; Gutierrez, Enrique; Cheema, Asim N; Serra, Vicenç; Amat-Santos, Ignacio J; Kefer, Joelle; Benitez, Luis Miguel; Leclercq, Florence; Mangieri, Antonio; Le Breton, Hervé; Jiménez-Quevedo, Pilar; Garcia Del Blanco, Bruno; Dager, Antonio; Abdul-Jawad Altisent, Omar; Puri, Rishi; Pibarot, Philippe; Rodés-Cabau, Josep

2018-05-01

To evaluate the changes in transvalvular gradients and the incidence of valve haemodynamic deterioration (VHD) following transcatheter aortic valve replacement (TAVR), according to use of anticoagulation therapy. This multicentre study included 2466 patients (46% men; mean age 81±7 years) who underwent TAVR with echocardiography performed at 12-month follow-up. Anticoagulation therapy was used in 707 patients (28.7%) following TAVR (AC group). A total of 663 patients received vitamin K antagonists, and 44 patients received direct oral anticoagulants. A propensity score matching analysis was performed to adjust for intergroup (AC vs non-AC post-TAVR) differences. A total of 622 patients per group were included in the propensity-matched analysis. VHD was defined as a ≥10 mm Hg increase in the mean transprosthetic gradient at follow-up (vs hospital discharge). The mean clinical follow-up was 29±18 months. The mean transvalvular gradient significantly increased at follow-up in the non-AC group within the global cohort (P=0.003), whereas it remained stable over time in the AC group (P=0.323). The incidence of VHD was significantly lower in the AC group (0.6%) compared with the non-AC group (3.7%, P<0.001), and these significant differences remained within the propensity-matched populations (0.6% vs 3.9% in the AC and non-AC groups, respectively, P<0.001). The occurrence of VHD did not associate with an increased risk of all-cause death (P=0.468), cardiovascular death (P=0.539) or stroke (P=0.170) at follow-up. The lack of anticoagulation therapy post-TAVR was associated with significant increments in transvalvular gradients and a greater risk of VHD. VHD was subclinical in most cases and did not associate with major adverse clinical events. Future randomised trials are needed to determine if systematic anticoagulation therapy post-TAVR would reduce the incidence of VHD. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article

Development of a radioimmunoassay for 'Tamm-Horsfall-like' glycoprotein in serum and cerebrospinal fluid

International Nuclear Information System (INIS)

Hartmann, L.; Bringuier, A.-F.; Schuller, E.

1983-01-01

Affinity chromatography purification was combined with a radioimmunoassay for 'Tamm-Horsfall-like' glycoprotein. This enabled serum comcentrations to be established and to demonstrate its presence in cerebrospinal fluid for the first time. This assay method used in different circumstances suggests a multifocal synthesis. Nevertheless, urinary Tamm-Horsfall glycoprotein so far must be distinguished from the serum or cerebrospinal fluid Tamm-Horsfall-like glycoprotein. (Auth.)

Evaluation of computerized decision support for oral anticoagulation management based in primary care.

Science.gov (United States)

Fitzmaurice, D A; Hobbs, F D; Murray, E T; Bradley, C P; Holder, R

1996-09-01

Increasing indications for oral anticoagulation has led to pressure on general practices to undertake therapeutic monitoring. Computerized decision support (DSS) has been shown to be effective in hospitals for improving clinical management. Its usefulness in primary care has previously not been investigated. To test the effectiveness of using DSS for oral anticoagulation monitoring in primary care by measuring the proportions of patients adequately controlled, defined as within the appropriate therapeutic range of International Normalised Ratio (INR). All patients receiving warfarin from two Birmingham inner city general practices were invited to attend a practice-based anticoagulation clinic. In practice A all patients were managed using DSS. In practice B patients were randomized to receive dosing advice either through DSS or through the local hospital laboratory. Clinical outcomes, adverse events and patient acceptability were recorded. Forty-nine patients were seen in total. There were significant improvements in INR control from 23% to 86% (P > 0.001) in the practice where all patients received dosing through DSS. In the practice where patients were randomized to either DSS or hospital dosing, logistic regression showed a significant trend for improvement in intervention patients which was not apparent in the hospital-dosed patients (P DSS through the full 12 months (24 days to 36 days) (P = 0.033). Adverse events were comparable between hospital and practice-dosed patients, although a number of esoteric events occurred. Patient satisfaction with the practice clinics was high. Computerized DSS enables the safe and effective transfer of anticoagulation management from hospital to primary care and may result in improved patient outcome in terms of the level of control, frequency of review and general acceptability.

Spatial localization of the Ebola virus glycoprotein mucin-like domain determined by cryo-electron tomography.

Science.gov (United States)

Tran, Erin E H; Simmons, James A; Bartesaghi, Alberto; Shoemaker, Charles J; Nelson, Elizabeth; White, Judith M; Subramaniam, Sriram

2014-09-01

The Ebola virus glycoprotein mucin-like domain (MLD) is implicated in Ebola virus cell entry and immune evasion. Using cryo-electron tomography of Ebola virus-like particles, we determined a three-dimensional structure for the full-length glycoprotein in a near-native state and compared it to that of a glycoprotein lacking the MLD. Our results, which show that the MLD is located at the apex and the sides of each glycoprotein monomer, provide a structural template for analysis of MLD function. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Inhibition of adhesion breast cancer cells by anticoagulant drugs and cimetidine

Czech Academy of Sciences Publication Activity Database

Bobek, V.; Boubelík, Michael; Kovařík, J.; Taltynov, O.

2003-01-01

Roč. 50, č. 2 (2003), s. 148-151 ISSN 0028-2685 Institutional research plan: CEZ:AV0Z5052915 Keywords : cimetidine * breast cancer * anticoagulants Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.782, year: 2003

Percutaneous left atrial appendage occlusion in atrial fibrillation patients with a contraindication to oral anticoagulation: a focused review.

Science.gov (United States)

Nishimura, Marin; Sab, Shiv; Reeves, Ryan R; Hsu, Jonathan C

2017-12-08

Stroke is the most feared complication of atrial fibrillation (AF). Although oral anticoagulation with non-vitamin K antagonist and non-vitamin K antagonist oral anticoagulants (NOACs) have been established to significantly reduce risk of stroke, real-world use of these agents are often suboptimal due to concerns for adverse events including bleeding from both patients and clinicians. Particularly in patients with previous serious bleeding, oral anticoagulation may be contraindicated. Left atrial appendage occlusion (LAAO), mechanically targeting the source of most of the thrombi in AF, holds an immense potential as an alternative to OAC in management of stroke prophylaxis. In this focused review, we describe the available evidence of various LAAO devices, detailing data regarding their use in patients with a contraindication for oral anticoagulation. Although some questions of safety and appropriate use of these new devices in patients who cannot tolerate anticoagulation remain, LAAO devices offer a significant step forward in the management of patients with AF, including those patients who may not be able to be prescribed OAC at all. Future studies involving patients fully contraindicated to OAC are warranted in the era of LAAO devices for stroke risk reduction. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

A Carbohydrate Moiety of Secreted Stage-Specific Glycoprotein 4 Participates in Host Cell Invasion by Trypanosoma cruzi Extracellular Amastigotes

Directory of Open Access Journals (Sweden)

Pilar T. V. Florentino

2018-04-01

Full Text Available Trypanosoma cruzi is the etiologic agent of Chagas’ disease. It is known that amastigotes derived from trypomastigotes in the extracellular milieu are infective in vitro and in vivo. Extracellular amastigotes (EAs have a stage-specific surface antigen called Ssp-4, a GPI-anchored glycoprotein that is secreted by the parasites. By immunoprecipitation with the Ssp-4-specific monoclonal antibodies (mAb 2C2 and 1D9, we isolated the glycoprotein from EAs. By mass spectrometry, we identified the core protein of Ssp-4 and evaluated mRNA expression and the presence of Ssp-4 carbohydrate epitopes recognized by mAb1D9. We demonstrated that the carbohydrate epitope recognized by mAb1D9 could promote host cell invasion by EAs. Although infectious EAs express lower amounts of Ssp-4 compared with less-infectious EAs (at the mRNA and protein levels, it is the glycosylation of Ssp-4 (identified by mAb1D9 staining only in infectious strains and recognized by galectin-3 on host cells that is the determinant of EA invasion of host cells. Furthermore, Ssp-4 is secreted by EAs, either free or associated with parasite vesicles, and can participate in host-cell interactions. The results presented here describe the possible role of a carbohydrate moiety of T. cruzi surface glycoproteins in host cell invasion by EA forms, highlighting the potential of these moieties as therapeutic and vaccine targets for the treatment of Chagas’ disease.

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

Directory of Open Access Journals (Sweden)

Soo Hyun Lee

2016-05-01

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

Improved circulating microparticle analysis in acid-citrate dextrose (ACD) anticoagulant tube.

Science.gov (United States)

György, Bence; Pálóczi, Krisztina; Kovács, Alexandra; Barabás, Eszter; Bekő, Gabriella; Várnai, Katalin; Pállinger, Éva; Szabó-Taylor, Katalin; Szabó, Tamás G; Kiss, Attila A; Falus, András; Buzás, Edit I

2014-02-01

Recently extracellular vesicles (exosomes, microparticles also referred to as microvesicles and apoptotic bodies) have attracted substantial interest as potential biomarkers and therapeutic vehicles. However, analysis of microparticles in biological fluids is confounded by many factors such as the activation of cells in the blood collection tube that leads to in vitro vesiculation. In this study we aimed at identifying an anticoagulant that prevents in vitro vesiculation in blood plasma samples. We compared the levels of platelet microparticles and non-platelet-derived microparticles in platelet-free plasma samples of healthy donors. Platelet-free plasma samples were isolated using different anticoagulant tubes, and were analyzed by flow cytometry and Zymuphen assay. The extent of in vitro vesiculation was compared in citrate and acid-citrate-dextrose (ACD) tubes. Agitation and storage of blood samples at 37 °C for 1 hour induced a strong release of both platelet microparticles and non-platelet-derived microparticles. Strikingly, in vitro vesiculation related to blood sample handling and storage was prevented in samples in ACD tubes. Importantly, microparticle levels elevated in vivo remained detectable in ACD tubes. We propose the general use of the ACD tube instead of other conventional anticoagulant tubes for the assessment of plasma microparticles since it gives a more realistic picture of the in vivo levels of circulating microparticles and does not interfere with downstream protein or RNA analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Comparison of quality and hemorragic risk of oral anticoagulant therapy using acenocoumarol versus warfarin].

Science.gov (United States)

Oliva Berini, Elvira; Galán Alvarez, Pilar; Pacheco Onrubia, Ana María

2008-06-21

Long half life oral anticoagulants have shown a higher anticoagulation stability and a lower hemorragic risk than those of a short half life. We have compared therapeutic stability and hemorragic risk of acenocoumarol versus warfarin in 2 groups of patients on preventive anticoagulation because of atrial fibrilation (international normalised ratio [INR]: 2-3). Data on 120 patients treated with acenocoumarol and 120 on warfarin treatment who had started and continued treatment in our hospital for a minimum of a year was collected. The percentage of visits within the intended range of INR (2 to 3) was 65.5% with warfarin and 63.4% with acenocoumarol. Thirty percent of patients on warfarin had 75% or more of their controls within range, while for those treated with acenocoumarol this percentage was 22.5%. In the acenocoumarol group, 0.3 visits/patient/year presented an INR > or = 6 versus 0.07 in the warfarin group (p = 0.003). Patients treated with acenocoumarol show a higher risk of presenting with an INR > or = 6, but no statistically significant differences are observed in therapeutic stability.

Glycoproteins functionalized natural and synthetic polymers for prospective biomedical applications: A review.

Science.gov (United States)

Tabasum, Shazia; Noreen, Aqdas; Kanwal, Arooj; Zuber, Mohammad; Anjum, Muhammad Naveed; Zia, Khalid Mahmood

2017-05-01

Glycoproteins have multidimensional properties such as biodegradability, biocompatibility, non-toxicity, antimicrobial and adsorption properties; therefore, they have wide range of applications. They are blended with different polymers such as chitosan, carboxymethyl cellulose (CMC), polyvinyl pyrrolidone (PVP), polycaprolactone (PCL), heparin, polystyrene fluorescent nanoparticles (PS-NPs) and carboxyl pullulan (PC) to improve their properties like thermal stability, mechanical properties, resistance to pH, chemical stability and toughness. Considering the versatile charateristics of glycoprotein based polymers, this review sheds light on synthesis and characterization of blends and composites of glycoproteins, with natural and synthetic polymers and their potential applications in biomedical field such as drug delivery system, insulin delivery, antimicrobial wound dressing uses, targeting of cancer cells, development of anticancer vaccines, development of new biopolymers, glycoproteome research, food product and detection of dengue glycoproteins. All the technical scientific issues have been addressed; highlighting the recent advancement. Copyright © 2017 Elsevier B.V. All rights reserved.

Preparation of 131I-asialo-α1-acid glycoprotein

International Nuclear Information System (INIS)

Rijk, P.P. van

1975-01-01

α 1 -Acid glycoprotein (orosomucoid) was prepared from a byproduct of the ethanol plasma fractionation by means of ion-exchange procedures. Immunoelectrophoresis suggested a high degree of purity; the purified protein contained 13.5% sialic acid and 17.8% hexose. The α 1 -acid glycoprotein was modified by removal of sialic acid with neurominidase (E.C. 3.2.1.18) followed by iodination with 131 I. The purpose of the preparation, its potential use as a pharmacon for liver-function studies in nuclear medicine, is the subject of further study

Anticoagulant resistance: a relevant issue in sewer rat (Rattus norvegicus) control?

DEFF Research Database (Denmark)

Heiberg, Ann-Charlotte

2009-01-01

the resistant rats, had resistance-related mutations in the VKORC1 gene. CONCLUSION: The results of this study suggest that the genetic background of anticoagulant resistance may have to be redefined in respect of resistance-related changes in the VKORC1 gene. Copyright © 2009 Society of Chemical Industry......BACKGROUND: The majority of rat problems in cities are thought to be related to defective sewers, and the use of anticoagulant rodenticides in such places is often implemented as part of regular urban rodent control. Knowledge pertaining to the resistance status of sewer rat populations is non......-existent, which may be leading to control problems in cities. It has become crucial to provide knowledge on the prevalence of resistance and how different control strategies have affected its prevalence among sewer rat populations. The prevalence of resistance was investigated in six sewer locations in Copenhagen...

Quantitative method for analysis of six anticoagulant rodenticides in faeces, applied in a case with repeated samples from a dog.

Science.gov (United States)

Seljetun, Kristin Opdal; Eliassen, Elin; Karinen, Ritva; Moe, Lars; Vindenes, Vigdis

2018-01-17

Accidental poisoning with anticoagulant rodenticides is not uncommon in dogs, but few reports of the elimination kinetics and half-lives in this species have been published. Our objectives were to develop and validate a new method for the quantification of anticoagulant rodenticides in canine blood and faeces using reversed phase ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and apply the method on a case of anticoagulant rodenticide intoxication. Sample preparation was liquid-liquid extraction. Six anticoagulant rodenticides were separated using a UPLC ® BEH C 18 -column with a mobile phase consisting of 5 mM ammonium formate buffer pH 10.2 and methanol. MS/MS detection was performed with positive electrospray ionization and two multiple reaction monitoring transitions. The limits of quantification were set at the levels of the lowest calibrator (1.5-2.7 ng/mL or ng/g). The method was successfully applied to a case from a dog accidentally poisoned with anticoagulant rodenticide. Coumatetralyl and brodifacoum concentrations were determined from serial blood and faecal samples. A terminal half-life of at least 81 days for coumatetralyl in blood was estimated, which is longer than previous reported in other species. A slow elimination of brodifacoum from the faeces was found, with traces still detectable in the faeces at day 513. This study offers a new method of detection and quantification of six frequently used anticoagulant rodenticides in canine faeces. Such drugs might cause serious health effects and it is important to be able to detect these drugs, to initiate proper treatment. The very long elimination half-lives detected in our study is important to be aware of in assessment of anticoagulant rodenticide burden to the environment.

Efficacy and Safety of Non-Vitamin K Antagonist Oral Anticoagulants versus Vitamin K Antagonist Oral Anticoagulants in Patients Undergoing Radiofrequency Catheter Ablation of Atrial Fibrillation: A Meta-Analysis.

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Giuseppe Santarpia

Full Text Available Use of the non-vitamin K antagonist oral anticoagulants (NOACs is endorsed by current guidelines for stroke prevention in patients with atrial fibrillation (AF. However efficacy and safety of NOACs in patients undergoing catheter ablation (RFCA of AF has not been well established yet.To perform a meta-analysis of all studies comparing NOACs and vitamin K antagonist oral anticoagulants (VKAs in patients undergoing RFCA.Studies were searched for in PubMed and Google Scholar databases.Studies were considered eligible if: they evaluated the clinical impact of NOACs versus VKAs; they specifically analyzed the use of anticoagulants during periprocedural phase of RFCA; they reported clinical outcome data.25 studies were selected, including 9881 cases. The summary measure used was the risk ratio (RR with 95% confidence interval (CI. The random-effects or the fixed effect model were used to synthesize results from the selected studies.There was no significant difference in thromboembolic complications (RR 1.39; p=0.13. Bleeding complications were significantly lower in the NOACs-treated arm as compared to VKAs (RR=0.67, p<0.001. Interestingly, a larger number of thromboembolic events was found in the VKAs-treated arm in those studies where VKAs had been interrupted during the periprocedural phase (RR=0.68; p=ns. In this same subgroup a significantly higher incidence of both minor (RR=0.54; p=0.002 and major bleeding (RR=0.41; p=0.01 events was recorded. Conversely, the incidence of thromboembolic events in the VKAs-treated arm was significantly lower in those studies with uninterrupted periprocedural anticoagulation treatment (RR=1.89; p=0.02.As with every meta-analysis, no patients-level data were available.The use of NOACs in patients undergoing RFCA is safe, given the lower incidence of bleedings observed with NOACs. On the other side, periprocedural interruption of VKAs and bridging with heparin is associated with a higher bleeding rate with no

Mechanisms for lymphocytic choriomeningitis virus glycoprotein cleavage, transport, and incorporation into virions

International Nuclear Information System (INIS)

Kunz, Stefan; Edelmann, Kurt H.; Torre, Juan-Carlos de la; Gorney, Robert; Oldstone, Michael B.A.

2003-01-01

The glycoprotein (GP) of lymphocytic choriomeningitis virus (LCMV) serves as virus attachment protein to its receptor on host cells and is a key determinant for cell tropism, pathogenesis, and epidemiology of the virus. The GP of LCMV is posttranslationally cleaved by the subtilase SKI-1/S1P into two subunits, the peripheral GP1, which is implicated in receptor binding, and the transmembrane GP2 that is structurally similar to the fusion active membrane proximal portions of the glycoproteins of other enveloped viruses. The present study shows that cleavage by SKI-1/S1P is not required for cell surface expression of LCMVGP on infected cells but is essential for its incorporation into virions and for the production of infectious virus particles. In absence of SKI-1/S1P cleavage, cell-to-cell propagation of the virus was markedly reduced. Further, proteolytic processing of LCMVGP depends on the presence of a cluster of basic amino acids at the C-terminus of the cytoplasmic domain of GP2, a structural motif that is conserved in Old World arenaviruses. The effect of the truncation of the cytoplasmic tail on cleavage suggests a structural interdependence between the cytoplasmic domain and the ectodomains of LCMVGP

Feasibility Study of a Mobile Health Intervention for Older Adults on Oral Anticoagulation Therapy

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Jung-Ah Lee PhD, RN

2016-10-01

Full Text Available Background: Oral anticoagulation treatment (OAT such as warfarin therapy is recommended for older adults with atrial fibrillation, heart failure, or who are at risk for venous thromboembolism. Despite its proven benefits, older adults report both dissatisfaction with OAT and reduced quality of life that can potentially lead to low adherence to OAT and decreased treatment efficacy. Objective: To test the feasibility of Mobile Applications for Seniors to enhance Safe anticoagulation therapy (MASS, a mobile-based health technology intervention designed to promote independence and self-care. Method s: This pilot study used a single-arm experimental pre–post design to test the feasibility of a 3-month intervention using MASS in 18 older adults (male: n = 14; White: n = 9; Hispanic: n = 7; Other: n = 2; M age = 67. MASS was available in English or Spanish. Participants completed surveys about their OAT knowledge, attitudes, quality of life with OAT, and adherence at baseline and at a 3-month follow-up. Satisfaction with the MASS intervention was also assessed at follow-up. Results: Anticoagulation knowledge significantly improved from baseline to follow-up ( M base = 12.5 ± 5.51, M follow-up = 14.78 ± 3.93, p = .007. Other outcomes were not different, pre- and post-tests. Participants reported they were generally satisfied with MASS, its ease of use and its usefulness. Conclusion: The results showed use of MASS improved older adults’ knowledge of OAT. Using mHealth apps may enhance self-care among older adults with chronic conditions who are also taking oral anticoagulants.

Isolation of glycoproteins from brown algae

DEFF Research Database (Denmark)

2015-01-01

The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme...

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

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Rick H. van Gorp

2015-11-01

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

Genetic analysis of heptad-repeat regions in the G2 fusion subunit of the Junin arenavirus envelope glycoprotein

International Nuclear Information System (INIS)

York, Joanne; Agnihothram, Sudhakar S.; Romanowski, Victor; Nunberg, Jack H.

2005-01-01

The G2 fusion subunit of the Junin virus envelope glycoprotein GP-C contains two hydrophobic heptad-repeat regions that are postulated to form a six-helix bundle structure required for the membrane fusion activity of Class I viral fusion proteins. We have investigated the role of these heptad-repeat regions and, specifically, the importance of the putative interhelical a and d position sidechains by using alanine-scanning mutagenesis. All the mutant glycoproteins were expressed and transported to the cell surface. Proteolytic maturation at the subtilisin kexin isozyme-1/site-1-protease (SKI-1/S1P) cleavage site was observed in all but two of the mutants. Among the adequately cleaved mutant glycoproteins, four positions in the N-terminal region (I333, L336, L347 and L350) and two positions in the C-terminal region (R392 and W395) were shown to be important determinants of cell-cell fusion. Taken together, our results indicate that α-helical coiled-coil structures are likely critical in promoting arenavirus membrane fusion. These findings support the inclusion of the arenavirus GP-C among the Class I viral fusion proteins and suggest pharmacologic and immunologic strategies for targeting arenavirus infection and hemorrhagic fever

Molecular cloning and expression of cDNA encoding a lumenal calcium binding glycoprotein from sarcoplasmic reticulum

International Nuclear Information System (INIS)

Leberer, E.; Charuk, J.H.M.; MacLennan, D.H.; Green, N.M.

1989-01-01

Antibody screening was used to isolate a cDNA encoding the 160-kDa glycoprotein of rabbit skeletal muscle sarcoplasmic reticulum. The cDNA is identical to that encoding the 53-kDa glycoprotein except that it contains an in-frame insertion of 1,308 nucleotides near its 5' end, apparently resulting from alternative splicing. The protein encoded by the cDNA would contain a 19-residue NH 2 -terminal signal sequence and a 453-residue COOH-terminal sequence identical to the 53-kDa glycoprotein. It would also contain a 436-amino acid insert between these sequences. This insert would be highly acidic, suggesting that it might bind Ca 2+ . The purified 160-kDa glycoprotein and the glycoprotein expressed in COS-1 cells transfected with cDNA encoding the 160-kDa glycoprotein were shown to bind 45 C 2+ in a gel overlay assay. The protein was shown to be located in the lumen of the sarcoplasmic reticulum and to be associated through Ca 2+ with the membrane. The authors propose that this lumenal Ca 2+ binding glycoprotein of the sarcoplasmic reticulum be designated sarcalumenin

Discontinuation risk comparison among 'real-world' newly anticoagulated atrial fibrillation patients

DEFF Research Database (Denmark)

Lip, Gregory Y H; Pan, Xianying; Kamble, Shital

2018-01-01

Discontinuation of oral anticoagulants may expose non-valvular atrial fibrillation (NVAF) patients to an increased risk of stroke. This study describes the real-world discontinuation rates and compared the risk of drug discontinuation among NVAF patients initiating apixaban, warfarin, dabigatran,...

Recommendations for the anticoagulation of pregnant patients with mechanical heart valves

NARCIS (Netherlands)

Schapkaitz, Elise; Jacobson, Barry Frank; Manga, Pravin; Chitsike, Rufaro Saeed; Benade, Estee; Haas, Sylvia; Buller, Harry R.

2015-01-01

The management of pregnant patients with mechanical heart valves remains challenging because there are no large randomised studies to provide guidelines for effective anticoagulant therapy. Both vitamin K antagonists and heparins may be associated with maternal and foetal adverse events. The

Australine, a pyrrolizidine alkaloid that inhibits amyloglucosidase and glycoprotein processing

International Nuclear Information System (INIS)

Tropea, J.E.; Molyneux, R.J.; Kaushal, G.P.; Pan, Y.T.; Mitchell, M.; Elbein, A.D.

1989-01-01

Australine is a polyhydroxylated pyrrolizidine alkaloid that was isolated from the seeds of the Australian tree Castanospermum australe and characterized by NMR and X-ray diffraction analysis. Since swainsonine and catanospermine are polyhydroxylated indolizidine alkaloids that inhibit specific glycosidases, the authors tested australine against a variety of exoglycosidases to determine whether it would inhibit any of these enzymes. This alkaloid proved to be a good inhibitor of the α-glucosidase amyloglucosidase (50% inhibition at 5.8 μM), but it did not inhibit β-glucosidase, α- or β-mannosidase, or α- or β-galactosidase. The inhibition of amyloglucosidase was of a competitive nature. Australine also inhibited the glycoprotein processing enzyme glucosidase I, but had only slight activity toward glucosidase II. When incubated with cultured cells, this alkaloid inhibited glycoprotein processing at the glucosidase I step and caused the accumulation of glycoproteins with Glc 3 Man 7-9 (GlcNAc) 2 -oligosaccharides

Antiphospholipid antibody profile based obstetric outcomes of primary antiphospholipid syndrome: the PREGNANTS study.

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Saccone, Gabriele; Berghella, Vincenzo; Maruotti, Giuseppe Maria; Ghi, Tullio; Rizzo, Giuseppe; Simonazzi, Giuliana; Rizzo, Nicola; Facchinetti, Fabio; Dall'Asta, Andrea; Visentin, Silvia; Sarno, Laura; Xodo, Serena; Bernabini, Dalila; Monari, Francesca; Roman, Amanda; Eke, Ahizechukwu Chigoziem; Hoxha, Ariela; Ruffatti, Amelia; Schuit, Ewoud; Martinelli, Pasquale

2017-05-01

Antiphospholipid syndrome is an autoimmune, hypercoagulable state that is caused by antiphospholipid antibodies. Anticardiolipin antibodies, anti-β2 glycoprotein-I, and lupus anticoagulant are the main autoantibodies found in antiphospholipid syndrome. Despite the amassed body of clinical knowledge, the risk of obstetric complications that are associated with specific antibody profile has not been well-established. The purpose of this study was to assess the risk of obstetric complications in women with primary antiphospholipid syndrome that is associated with specific antibody profile. The Pregnancy In Women With Antiphospholipid Syndrome study is a multicenter, retrospective, cohort study. Diagnosis and classification of antiphospholipid syndrome were based on the 2006 International revised criteria. All women included in the study had at least 1 clinical criteria for antiphospholipid syndrome, were positive for at least 1 antiphospholipid antibody (anticardiolipin antibodies, anti-β2 glycoprotein-I, and/or lupus anticoagulant), and were treated with low-dose aspirin and prophylactic low molecular weight heparin from the first trimester. Only singleton pregnancies with primary antiphospholipid syndrome were included. The primary outcome was live birth, defined as any delivery of a live infant after 22 weeks gestation. The secondary outcomes were preeclampsia with and without severe features, intrauterine growth restriction, and stillbirth. We planned to assess the outcomes that are associated with the various antibody profile (test result for lupus anticoagulant, anticardiolipin antibodies, and anti-β2 glycoprotein-I). There were 750 singleton pregnancies with primary antiphospholipid syndrome in the study cohort: 54 (7.2%) were positive for lupus anticoagulant only; 458 (61.0%) were positive for anticardiolipin antibodies only; 128 (17.1%) were positive for anti-β2 glycoprotein-I only; 90 (12.0%) were double positive and lupus anticoagulant negative, and 20

Outcome after discontinuing anticoagulant therapy in women with venous thromboembolism during hormonal use.

Science.gov (United States)

Blanco-Molina, Ángeles; Trujillo-Santos, Javier; Pesavento, Raffaele; Rosa, Vladimir; Falgá, Conxita; Tolosa, Carles; Mazzolai, Lucia; Sampériz, Ángel; Duce, Rita; Monreal, Manuel

2017-03-01

Whether women developing venous thromboembolism (VTE) while using hormonal therapy should be classified as having "unprovoked" or "provoked" VTE is controversial. We used the RIETE (Registro Informatizado Enfermedad TromboEmbólica) database to compare the rate of symptomatic VTE recurrences after discontinuing anticoagulation in 3 subgroups of women aged ≤50years without cancer, pregnancy or puerperium: (1) those with hormonal therapy and no additional risk factors (hormonal users only); (2) those with unprovoked VTE; and (3) those with additional risk factors, with or without hormonal therapy. As of March 2016, 1513 women had been followed-up for at least one month after discontinuing anticoagulation. Of these, 654 (43%) were hormonal users only, 390 (26%) had unprovoked VTE and 469 (31%) had transient risk factors with or without hormonal therapy. After discontinuing anticoagulation, the rate of VTE recurrences in women with hormonal use only (2.44 per 100 patient-years; 95% CI: 1.53-3.69) was significantly lower than in those with unprovoked VTE (6.03; 95% CI: 3.97-8.77) and similar to those with transient risk factors (2.58; 95% CI: 1.50-4.13). Interestingly, the rate of VTE recurrences presenting as pulmonary embolism in women with hormonal use only (0.55 per 100 patient-years; 95% CI: 0.18-1.29) was similar to those with transient risk factors (0.46; 95% CI: 0.09-1.33) and 4-fold lower than in women with unprovoked VTE (2.23; 95% CI: 1.07-4.10). After discontinuing anticoagulation, the rate of VTE recurrences in hormonal users only was significantly lower than in women with unprovoked VTE and similar to the rate in women with additional risk factors. © 2017 Elsevier Ltd. All rights reserved.

A network-based multi-target computational estimation scheme for anticoagulant activities of compounds.

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Qian Li

Full Text Available BACKGROUND: Traditional virtual screening method pays more attention on predicted binding affinity between drug molecule and target related to a certain disease instead of phenotypic data of drug molecule against disease system, as is often less effective on discovery of the drug which is used to treat many types of complex diseases. Virtual screening against a complex disease by general network estimation has become feasible with the development of network biology and system biology. More effective methods of computational estimation for the whole efficacy of a compound in a complex disease system are needed, given the distinct weightiness of the different target in a biological process and the standpoint that partial inhibition of several targets can be more efficient than the complete inhibition of a single target. METHODOLOGY: We developed a novel approach by integrating the affinity predictions from multi-target docking studies with biological network efficiency analysis to estimate the anticoagulant activities of compounds. From results of network efficiency calculation for human clotting cascade, factor Xa and thrombin were identified as the two most fragile enzymes, while the catalytic reaction mediated by complex IXa:VIIIa and the formation of the complex VIIIa:IXa were recognized as the two most fragile biological matter in the human clotting cascade system. Furthermore, the method which combined network efficiency with molecular docking scores was applied to estimate the anticoagulant activities of a serial of argatroban intermediates and eight natural products respectively. The better correlation (r = 0.671 between the experimental data and the decrease of the network deficiency suggests that the approach could be a promising computational systems biology tool to aid identification of anticoagulant activities of compounds in drug discovery. CONCLUSIONS: This article proposes a network-based multi-target computational estimation

A network-based multi-target computational estimation scheme for anticoagulant activities of compounds.

Science.gov (United States)

Li, Qian; Li, Xudong; Li, Canghai; Chen, Lirong; Song, Jun; Tang, Yalin; Xu, Xiaojie

2011-03-22

Traditional virtual screening method pays more attention on predicted binding affinity between drug molecule and target related to a certain disease instead of phenotypic data of drug molecule against disease system, as is often less effective on discovery of the drug which is used to treat many types of complex diseases. Virtual screening against a complex disease by general network estimation has become feasible with the development of network biology and system biology. More effective methods of computational estimation for the whole efficacy of a compound in a complex disease system are needed, given the distinct weightiness of the different target in a biological process and the standpoint that partial inhibition of several targets can be more efficient than the complete inhibition of a single target. We developed a novel approach by integrating the affinity predictions from multi-target docking studies with biological network efficiency analysis to estimate the anticoagulant activities of compounds. From results of network efficiency calculation for human clotting cascade, factor Xa and thrombin were identified as the two most fragile enzymes, while the catalytic reaction mediated by complex IXa:VIIIa and the formation of the complex VIIIa:IXa were recognized as the two most fragile biological matter in the human clotting cascade system. Furthermore, the method which combined network efficiency with molecular docking scores was applied to estimate the anticoagulant activities of a serial of argatroban intermediates and eight natural products respectively. The better correlation (r = 0.671) between the experimental data and the decrease of the network deficiency suggests that the approach could be a promising computational systems biology tool to aid identification of anticoagulant activities of compounds in drug discovery. This article proposes a network-based multi-target computational estimation method for anticoagulant activities of compounds by

The expression and serological reactivity of recombinant canine herpesvirus 1 glycoprotein D

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MarkéŽta Vaňkov‡á

2016-01-01

Full Text Available The aim of this work was to express recombinant glycoprotein D of canine herpesvirus 1 in bacterial cells and to evaluate its diagnostic sensitivity and specificity when compared to traditional serological methods. The gene fragment coding glycoprotein D of canine herpesvirus 1 was amplified by polymerase chain reaction, cloned into plasmid vector and expressed in Escherichia coli cells. Recombinant protein was then purified and used as an antigen in immunoblot for a detection of canine herpesvirus 1 specific antibodies. Antibody testing was performed on the panel of 100 canine sera by immunoblot with recombinant glycoprotein D as antigen and compared with indirect immunofluorescence assay. Serum samples were collected from 83 dogs with no history of canine herpesvirus 1 or reproductive disorders, and from 17 dogs from breeding kennels with a history of canine herpesvirus 1 related reproductive disorders. Sensitivity of glycoprotein D based immunoblot was 89.2% and specificity was 93%. Kappa value was calculated to be 0.8 between immunoblot and indirect immunofluorescence assay. Antibodies against canine herpesvirus 1 infection were detected in 33% of samples by immunoblot assay. Our study confirms that recombinant glycoprotein D expressed in bacterial cells could be used as a suitable and sensitive antigen for immunological tests and that herpesvirus infection seems to be common among the canine population in the Czech Republic.

The impact of pre-injury anticoagulation therapy in the older adult patient experiencing a traumatic brain injury: A systematic review.

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Smith, Karen; Weeks, Susan

2012-01-01

The objective of this systematic review is to synthesize the best available evidence on the impact of pre-injury anticoagulation therapy in the older adult patient who experiences a traumatic brain injury. Trauma in the elderly remains one of the most challenging problems for healthcare providers in the 21 century. The most recent United States (U.S.) census estimates that by the year 2020 more than 52 million Americans will be age 65 years or older, and one million of those will live to be over 100 years of age. In the older adult population, classified as age 65 years or greater, the two leading causes of injury were reported as motor vehicle crashes (MVC) and falls. We have become increasingly aware of the unique physiologic changes in this population that make them more susceptible to succumb to traumatic injuries than their younger counterparts. This is especially true in the anticoagulated patient with a traumatic brain injury.Traumatic brain injury (TBI) is defined as an injury occurring when an external force traumatizes the brain. It may also be known as an intracranial or head injury. TBI is classified depending on the mechanism of injury (blunt or penetrating), severity, and location of the assault. Damage to the brain, skull, and/or scalp transpires. TBI is the leading cause of death and disability in the U.S, and persons of all ages, races, ethnicities, and incomes are affected. In the past five to ten years, trauma services have recorded an increase in major trauma admissions of patients age 65 years and older. In review of the literature to date, it is recognized that outcomes following moderate to severe TBI in older adults are poor, with high rates of significant disability and mortality reported. A recent Australian study reported that 28% of older adults died in the hospital following a TBI and in Finland adults aged 75 years and older had the highest rates of TBI related hospitalizations and death. According to a systematic review of European

Andexanet alfa effectively reverses edoxaban anticoagulation effects and associated bleeding in a rabbit acute hemorrhage model

Science.gov (United States)

Lu, Genmin; Pine, Polly; Leeds, Janet M.; DeGuzman, Francis; Pratikhya, Pratikhya; Lin, Joyce; Malinowski, John; Hollenbach, Stanley J.; Curnutte, John T.

2018-01-01

Introduction Increasing use of factor Xa (FXa) inhibitors necessitates effective reversal agents to manage bleeding. Andexanet alfa, a novel modified recombinant human FXa, rapidly reverses the anticoagulation effects of direct and indirect FXa inhibitors. Objective To evaluate the ability of andexanet to reverse anticoagulation in vitro and reduce bleeding in rabbits administered edoxaban. Materials and methods In vitro studies characterized the interaction of andexanet with edoxaban and its ability to reverse edoxaban-mediated anti-FXa activity. In a rabbit model of surgically induced, acute hemorrhage, animals received edoxaban vehicle+andexanet vehicle (control), edoxaban (1 mg/kg)+andexanet vehicle, edoxaban+andexanet (75 mg, 5-minute infusion, 20 minutes after edoxaban), or edoxaban vehicle+andexanet prior to injury. Results Andexanet bound edoxaban with high affinity similar to FXa. Andexanet rapidly and dose-dependently reversed the effects of edoxaban on FXa activity and coagulation pharmacodynamic parameters in vitro. In edoxaban-anticoagulated rabbits, andexanet reduced anti-FXa activity by 82% (from 548±87 to 100±41 ng/ml; P<0.0001), mean unbound edoxaban plasma concentration by ~80% (from 100±10 to 21±6 ng/ml; P<0.0001), and blood loss by 80% vs. vehicle (adjusted for control, 2.6 vs. 12.9 g; P = 0.003). The reduction in blood loss correlated with the decrease in anti-FXa activity (r = 0.6993, P<0.0001) and unbound edoxaban (r = 0.5951, P = 0.0035). Conclusion These data demonstrate that andexanet rapidly reversed the anticoagulant effects of edoxaban, suggesting it could be clinically valuable for the management of acute and surgery-related bleeding. Correlation of blood loss with anti-FXa activity supports the use of anti-FXa activity as a biomarker for assessing anticoagulation reversal in clinical trials. PMID:29590221

Global site-specific analysis of glycoprotein N-glycan processing.

Science.gov (United States)

Cao, Liwei; Diedrich, Jolene K; Ma, Yuanhui; Wang, Nianshuang; Pauthner, Matthias; Park, Sung-Kyu Robin; Delahunty, Claire M; McLellan, Jason S; Burton, Dennis R; Yates, John R; Paulson, James C

2018-06-01

N-glycans contribute to the folding, stability and functions of the proteins they decorate. They are produced by transfer of the glycan precursor to the sequon Asn-X-Thr/Ser, followed by enzymatic trimming to a high-mannose-type core and sequential addition of monosaccharides to generate complex-type and hybrid glycans. This process, mediated by the concerted action of multiple enzymes, produces a mixture of related glycoforms at each glycosite, making analysis of glycosylation difficult. To address this analytical challenge, we developed a robust semiquantitative mass spectrometry (MS)-based method that determines the degree of glycan occupancy at each glycosite and the proportion of N-glycans processed from high-mannose type to complex type. It is applicable to virtually any glycoprotein, and a complete analysis can be conducted with 30 μg of protein. Here, we provide a detailed description of the method that includes procedures for (i) proteolytic digestion of glycoprotein(s) with specific and nonspecific proteases; (ii) denaturation of proteases by heating; (iii) sequential treatment of the glycopeptide mixture with two endoglycosidases, Endo H and PNGase F, to create unique mass signatures for the three glycosylation states; (iv) LC-MS/MS analysis; and (v) data analysis for identification and quantitation of peptides for the three glycosylation states. Full coverage of site-specific glycosylation of glycoproteins is achieved, with up to thousands of high-confidence spectra hits for each glycosite. The protocol can be performed by an experienced technician or student/postdoc with basic skills for proteomics experiments and takes ∼7 d to complete.

Dental Procedures in Patients with Atrial Fibrillation and New Oral Anticoagulants

Science.gov (United States)

2014-01-01

This review discusses the basic pharmacology of new oral anticoagulants that are used for prevention of thromboembolism in patients with atrial fibrillation. It presents available evidence, and provides recommendations for the management of patients requiring invasive procedures in dental practice. PMID:26835072

Mechanism of Binding to Ebola Virus Glycoprotein by the ZMapp, ZMAb, and MB-003 Cocktail Antibodies

OpenAIRE

Davidson, Edgar; Bryan, Christopher; Fong, Rachel H.; Barnes, Trevor; Pfaff, Jennifer M.; Mabila, Manu; Rucker, Joseph B.; Doranz, Benjamin J.

2015-01-01

Cocktails of monoclonal antibodies (MAbs) that target the surface glycoprotein (GP) of Ebola virus (EBOV) are effective in nonhuman primate models and have been used under emergency compassionate-treatment protocols in human patients. However, the amino acids that form the detailed binding epitopes for the MAbs in the ZMapp, ZMAb, and the related MB-003 cocktails have yet to be identified. Other binding properties that define how each MAb functionally interacts with GP—such as affinity, epito...

Analytical Pipeline for Discovery and Verification of Glycoproteins from Plasma-Derived Extracellular Vesicles as Breast Cancer Biomarkers.

Science.gov (United States)

Chen, I-Hsuan; Aguilar, Hillary Andaluz; Paez Paez, J Sebastian; Wu, Xiaofeng; Pan, Li; Wendt, Michael K; Iliuk, Anton B; Zhang, Ying; Tao, W Andy

2018-05-15

Glycoproteins comprise more than half of current FDA-approved protein cancer markers, but the development of new glycoproteins as disease biomarkers has been stagnant. Here we present a pipeline to develop glycoproteins from extracellular vesicles (EVs) through integrating quantitative glycoproteomics with a novel reverse phase glycoprotein array and then apply it to identify novel biomarkers for breast cancer. EV glycoproteomics show promise in circumventing the problems plaguing current serum/plasma glycoproteomics and allowed us to identify hundreds of glycoproteins that have not been identified in blood. We identified 1,453 unique glycopeptides representing 556 glycoproteins in EVs, among which 20 were verified significantly higher in individual breast cancer patients. We further applied a novel glyco-specific reverse phase protein array to quantify a subset of the candidates. Together, this study demonstrates the great potential of this integrated pipeline for biomarker discovery.

Homologous and heterologous antibody responses of mice immunized with purified feline herpesvirus type 1 and canine herpesvirus glycoproteins.

Science.gov (United States)

Limcumpao, J A; Horimoto, T; Xuan, X N; Tohya, Y; Azetaka, M; Takahashi, E; Mikami, T

1991-06-01

The three glycoproteins each of feline herpesvirus type 1 (FHV-1) and canine herpesvirus (CHV) were purified by affinity chromatography using glycoprotein-specific monoclonal antibodies and used individually or in combination in immunizing mice to determine their relative immunogenicity. All the glycoproteins induced detectable virus neutralizing antibodies to the homologous virus but FHV-1 gp143/108 and its cross-reacting counterpart, CHV gp145/112, elicited the highest titers not only to the homologous virus but to the heterologous virus as well. The production of ELISA antibodies after glycoprotein immunization was variable, while hemagglutination-inhibiting antibodies were produced by only 1 out of 10 FHV-1 gp60-inoculated mice. In general, the antibody titers induced by CHV glycoproteins were lower than those by FHV-1 glycoproteins. These results indicate that these glycoproteins may be useful as subunit vaccines against FHV-1 and CHV infections.

Managing direct oral anticoagulants in patients undergoing dentoalveolar surgery.

Science.gov (United States)

Patel, J P; Woolcombe, S A; Patel, R K; Obisesan, O; Roberts, L N; Bryant, C; Arya, R

2017-02-24

Our objective was to describe our experience of managing a cohort of adult patients prescribed direct oral anticoagulants (DOACs) undergoing dentoalveolar procedures between November 2012 and May 2016. Prior to conducting a procedure a formal assessment was made of each patient's anticoagulation treatment. A specific plan was then formulated, balancing the risk of bleeding with the risk of thrombosis. Patients received a telephone consultation one week following treatment to assess any post-operative bleeding. Eighty-two patients underwent 111 oral surgical procedures, the majority of which were dental extractions. In the case of 35 (32%) procedures, advice was given to omit the DOAC, either before or after treatment. There was no bleeding following the majority of procedures. Persistent bleeding followed 15 (13.5%) procedures, of which 7 (6.3%) procedures required specific intervention. The majority of patients prescribed DOACs can undergo dentoalveolar procedures safely. Important considerations when planning treatment are: (i) when the patient usually takes their dose of DOAC, (ii) the time the procedure is performed and, (iii) when the DOAC is taken post-procedure. In our experience, if these factors are considered carefully, omission of DOAC doses is unlikely to be required for most patients.

Haemorrhage in the labyrinth caused by anticoagulant therapy: case report

International Nuclear Information System (INIS)

Callonnec, F.; Gerardin, E.; Thiebot, J.; Marie, J.P.; Andrieu Guitrancourt, J.; Marsot-Dupuch, K.

1999-01-01

We report a patient who experienced a severe vertiginous episode with bilateral tinnitus and progressive right-sided hearing loss. She had Marfan's disease and was on anticoagulant treatment. The fluid in the labyrinth gave higher signal than cerebrospinal fluid on T1-weighted images, suggesting haemorrhage. The radiological follow-up is discussed. (orig.)

Portuguese Observational Study of Ischaemic Stroke in Patients Medicated with Non-Vitamin K Antagonist Oral Anticoagulants.

Science.gov (United States)

Beato-Coelho, José; Marto, João Pedro; Alves, José Nuno; Marques-Matos, Cláudia; Calado, Sofia; Araújo, José; Cunha, Luís; Pinho, João; Azevedo, Elsa; Viana-Baptista, Miguel; Sargento-Freitas, João

2018-01-01

Clinical trials and subsequent meta-analyses showed advantages of non-vitamin K antagonists oral anticoagulants (NOACs) over vitamin K antagonists (VKAs) in patients with non-valvular atrial fibrillation. The impact of preadmission anticoagulation in acute ischaemic stroke (AIS) has not been established. To compare functional outcome of patients with AIS with preadmission NOACs vs. VKAs. A retrospective analysis was conducted on consecutive AIS patients under oral anticoagulation (VKAs or NOACs) admitted in 4 Portuguese hospitals within a period of 30 months. Two primary outcomes were defined and compared between VKA and NOAC groups: symptomatic intracerebral hemorrhage transformation (sICH) and modified Rankin Scale (mRS) at 3 months. Four hundred sixty-nine patients were included, of whom 332 (70.8%) were treated with VKA and 137 (29.2%) with NOAC. Patients' median age was 78.0 and 234 (49.9%) were male. NOAC-treated patients had a higher median CHA2DS2-VASc score than those under VKA (5.0 vs. 4.0, p = 0.023). The two primary outcomes showed no statistical differences between the VKAs' group and the NOACs' group (sICH: 5.4 vs. 5.4% [p = 0.911]; mRS at 3 months: 3.0 vs. 3.0 [p = 0.646], respectively). Preadmission anticoagulation with NOACs in AIS has a functional impact similar to that of VKAs. © 2018 S. Karger AG, Basel.

Inactivated Recombinant Rabies Viruses Displaying Canine Distemper Virus Glycoproteins Induce Protective Immunity against Both Pathogens.

Science.gov (United States)

da Fontoura Budaszewski, Renata; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Yin, Xiangping; Schnell, Matthias J; von Messling, Veronika

2017-04-15

The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Both canine distemper virus (CDV) and rabies virus (RABV) cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wildlife species. In this study, we developed recombinant bivalent vaccine candidates based on recombinant vaccine strain rabies virus particles, which concurrently display the protective CDV and RABV glycoprotein antigens. The recombinant viruses replicated to near-wild-type titers, and the heterologous glycoproteins were efficiently expressed and incorporated in the viral particles. Immunization of ferrets with beta-propiolactone-inactivated recombinant virus particles elicited protective RABV antibody titers, and animals immunized with a combination of CDV attachment protein- and fusion protein-expressing recombinant viruses were protected from lethal CDV challenge. However, animals that were immunized with only a RABV expressing the attachment protein of CDV vaccine strain Onderstepoort succumbed to infection with a more recent wild-type strain, indicating that immune responses to the more conserved fusion protein contribute to protection against heterologous CDV strains. IMPORTANCE Rabies virus and canine distemper virus (CDV) cause high mortality rates and death in many carnivores. While rabies vaccines are inactivated and thus have an excellent safety profile and high stability, live-attenuated CDV vaccines can retain residual virulence in highly susceptible species. Here we generated recombinant inactivated rabies viruses that carry one of the CDV glycoproteins on their surface. Ferrets immunized twice with a mix of recombinant rabies viruses carrying the CDV fusion and attachment glycoproteins were protected from lethal CDV challenge, whereas all animals that received

Bioactivity of proteins isolated from Lactobacillus plantarum L67 treated with Zanthoxylum piperitum DC glycoprotein.

Science.gov (United States)

Song, S; Oh, S; Lim, K-T

2015-06-01

Lactobacilli in the human gastrointestinal tract have beneficial effects on the health of their host. To enhance these effects, the bioactivity of lactobacilli can be fortified through exogenous dietary or pharmacological agents, such as glycoproteins. To elucidate the inductive effect of Zanthoxylum piperitum DC (ZPDC) glycoprotein on Lactobacillus plantarum L67, we evaluated the radical-scavenging activity, anti-oxidative enzymes (SOD, GPx and CAT), growth rate, ATPase activity and β-galactosidase activity of this strain. When Lact. plantarum L67 was treated with ZPDC glycoprotein at different concentrations, the intensities of a few SDS-PAGE bands were slightly changed. The amount of a 23 kDa protein was increased upon treatment with increasing concentrations of ZPDC glycoprotein. The results of this study indicate that the radical-scavenging activity for O2(-) and OH¯, but not for the DPPH radical, increased in a concentration-dependent manner after treatment with ZPDC glycoprotein. The activation of anti-oxidative enzymes (SOD, GPx and CAT), growth rate and β-galactosidase activity also increased in a concentration-dependent manner in response to ZPDC glycoprotein treatment, whereas ATPase activity was decreased. In summary, ZPDC glycoprotein stimulated an increase in the bioactivity of Lact. plantarum L67. Significance and impact of the study: This study demonstrated that Lactobacillus plantarum L67 possesses anti-oxidative activity. This strain of lactic bacteria has been known to have various probiotic uses, such as yogurt starters and dietary additional supplements. We found, through this experiment, that the protein has a strong anti-oxidative character, and the activity can be enhanced by treatment with Zanthoxylum piperitum DC (ZPDC) glycoprotein. This study may be application of Lact. plantarum L67 treated by ZPDC glycoprotein in yogurt fermentation. It could be one of the avenues of minimizing yogurt postacidification during storage. In addition

Anticoagulation After Biological Aortic Valve Replacement: Is There An Optimal Regimen?

Science.gov (United States)

Owais, Tamer; Rouman, Mina; Breuer, Martin; Hüter, Lars; Fuchs, Jürgen; Lauer, Bernward; Kuntze, Thomas

2016-03-01

The anticoagulation of biological heart valves remains a 'hot spot' of discussion in various domains due to the risk of developing valve thrombosis and arterial thromboembolism. The situation has always been controversial, especially during the early postoperative phase. The American College of Cardiology/ American Heart Association and European Society of Cardiology guidelines recommend the use of warfarin for the first three months after biological aortic valve replacement (BAVR), although the American College of Chest Physicians guidelines suggest that these recommendations are experience-based and that the risk/benefit is unclear. The aim of the present study was to compare the efficacy of aspirin and warfarin in patients after BAVR. A total of 863 patients who underwent BAVR between 2008 and 2015 was allocated to two groups. Each group was managed with a specific anticoagulation regimen, with 430 patients receiving warfarin during the first three postoperative months, and 433 receiving aspirin. The major study end points were bleeding, cerebral ischemic events, and survival. In total, 10 and 15 postoperative cerebral ischemic events occurred between 24 h and three months after surgery in patients treated with aspirin and warfarin, respectively. After three months the incidence of cerebral ischemic events did not differ greatly between the two groups. The rate of major bleeding events and rates of stroke-free survival and overall survival were not statistically significant between the warfarin and aspirin groups. Plasma anticoagulation with warfarin during the early postoperative phase was shown statistically to be inferior to platelet aggregation inhibition by aspirin with regards to postoperative bleeding risk, cerebral ischemic events, and survival.

Choosing a particular oral anticoagulant and dose for stroke prevention in individual patients with non-valvular atrial fibrillation: part 1

NARCIS (Netherlands)

Diener, H.C.; Aisenberg, J.; Ansell, J.; Atar, D.; Breithardt, G.; Eikelboom, J.; Ezekowitz, M.D.; Granger, C.B.; Halperin, J.L.; Hohnloser, S.H.; Hylek, E.M.; Kirchhof, P.; Lane, D.A.; Verheugt, F.W.A.; Veltkamp, R.; Lip, G.Y.

2017-01-01

Patients with atrial fibrillation (AF) have a high risk of stroke and mortality, which can be considerably reduced by oral anticoagulants (OAC). Recently, four non-vitamin-K oral anticoagulants (NOACs) were compared with warfarin in large randomized trials for the prevention of stroke and systemic

Screening computer-assisted dosage programs for anticoagulation with warfarin and other vitamin K antagonists: minimum safety requirements for individual programs

DEFF Research Database (Denmark)

Poller, L; Roberts, C; Ibrahim, S

2009-01-01

Based on the results of the previous European Action on Anticoagulation (EAA) multicenter study, a simplified minimum procedure is described for screening the safety and effectiveness of marketed programs for dosage of oral anticoagulant drugs (vitamin K antagonists). The aim was to demonstrate non...

The haemagglutination activity of equine herpesvirus type 1 glycoprotein C.

Science.gov (United States)

Andoh, Kiyohiko; Hattori, Shiho; Mahmoud, Hassan Y A H; Takasugi, Maaya; Shimoda, Hiroshi; Bannai, Hiroshi; Tsujimura, Koji; Matsumura, Tomio; Kondo, Takashi; Kirisawa, Rikio; Mochizuki, Masami; Maeda, Ken

2015-01-02

Equine herpesvirus type 1 (EHV-1) has haemagglutination (HA) activity toward equine red blood cells (RBCs), but the identity of its haemagglutinin is unknown. To identify the haemagglutinin of EHV-1, the major glycoproteins of EHV-1 were expressed in 293T cells, and the cells or cell lysates were mixed with equine RBCs. The results showed that only EHV-1 glycoprotein C (gC)-producing cells adsorbed equine RBCs, and that the lysate of EHV-1 gC-expressing cells agglutinated equine RBCs. EHV-1 lacking gC did not show HA activity. HA activity was inhibited by monoclonal antibodies (MAbs) specific for gC, but not by antibodies directed against other glycoproteins. In addition, HA activity was not inhibited by the addition of heparin. These results indicate that EHV-1 gC can bind equine RBCs irrespective of heparin, in contrast to other herpesvirus gC proteins. Copyright © 2014 Elsevier B.V. All rights reserved.

Australine, a pyrrolizidine alkaloid that inhibits amyloglucosidase and glycoprotein processing

Energy Technology Data Exchange (ETDEWEB)

Tropea, J.E.; Molyneux, R.J.; Kaushal, G.P.; Pan, Y.T.; Mitchell, M.; Elbein, A.D. (Univ. of Texas Health Science Center, San Antonio (USA))

1989-03-07

Australine is a polyhydroxylated pyrrolizidine alkaloid that was isolated from the seeds of the Australian tree Castanospermum australe and characterized by NMR and X-ray diffraction analysis. Since swainsonine and catanospermine are polyhydroxylated indolizidine alkaloids that inhibit specific glycosidases, the authors tested australine against a variety of exoglycosidases to determine whether it would inhibit any of these enzymes. This alkaloid proved to be a good inhibitor of the {alpha}-glucosidase amyloglucosidase (50% inhibition at 5.8 {mu}M), but it did not inhibit {beta}-glucosidase, {alpha}- or {beta}-mannosidase, or {alpha}- or {beta}-galactosidase. The inhibition of amyloglucosidase was of a competitive nature. Australine also inhibited the glycoprotein processing enzyme glucosidase I, but had only slight activity toward glucosidase II. When incubated with cultured cells, this alkaloid inhibited glycoprotein processing at the glucosidase I step and caused the accumulation of glycoproteins with Glc{sub 3}Man{sub 7-9}(GlcNAc){sub 2}-oligosaccharides.

Shedding of Ebola Virus Surface Glycoprotein Is a Mechanism of Self-regulation of Cellular Cytotoxicity and Has a Direct Effect on Virus Infectivity.

Science.gov (United States)

Dolnik, Olga; Volchkova, Valentina A; Escudero-Perez, Beatriz; Lawrence, Philip; Klenk, Hans-Dieter; Volchkov, Viktor E

2015-10-01

The surface glycoprotein (GP) is responsible for Ebola virus (EBOV) attachment and membrane fusion during virus entry. Surface expression of highly glycosylated GP causes marked cytotoxicity via masking of a wide range of cellular surface molecules, including integrins. Considerable amounts of surface GP are shed from virus-infected cells in a soluble truncated form by tumor necrosis factor α-converting enzyme. In this study, the role of GP shedding was investigated using a reverse genetics approach by comparing recombinant viruses possessing amino acid substitutions at the GP shedding site. Virus with an L635V substitution showed a substantial decrease in shedding, whereas a D637V substitution resulted in a striking increase in the release of shed GP. Variations in shedding efficacy correlated with observed differences in the amounts of shed GP in the medium, GP present in virus-infected cells, and GP present on virions. An increase in shedding appeared to be associated with a reduction in viral cytotoxicity, and, vice versa, the virus that shed less was more cytotoxic. An increase in shedding also resulted in a reduction in viral infectivity, whereas a decrease in shedding efficacy enhanced viral growth characteristics in vitro. Differences in shedding efficacy and, as a result, differences in the amount of mature GP available for incorporation into budding virions did not equate to differences in overall release of viral particles. Likewise, data suggest that the resulting differences in the amount of mature GP on the cell surface led to variations in the GP content of released particles and, as a consequence, in infectivity. In conclusion, fine-tuning of the levels of EBOV GP expressed at the surface of virus-infected cells via GP shedding plays an important role in EBOV replication by orchestrating the balance between optimal virion GP content and cytotoxicity caused by GP. © The Author 2015. Published by Oxford University Press on behalf of the Infectious

Conservatively managed pineal apoplexy in an anticoagulated patient

International Nuclear Information System (INIS)

Werder, Gabriel M.; Razdan, Rahul S.; Gagliardi, Joseph A.; Chaddha, Shashi K.B.

2008-01-01

We present a case of pineal apoplexy in an anticoagulated and hypertensive 56-year-old Hispanic male. At presentation, the patient's international normalized ratio (INR) was 10.51 and his blood pressure was 200/130 mmHg. His presenting symptoms included acute onset of headache, chest pain, nausea, vomiting, vertigo, and visual disturbance. Neuroimaging demonstrated hemorrhage into a morphologically normal pineal gland. Under conservative management, the patient experienced gradual resolution of all symptoms excluding the disturbance of upward gaze

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.

Study of the role of the covalently linked cell wall protein (Ccw14p) and yeast glycoprotein (Ygp1p) within biofilm formation in a flor yeast strain.

Science.gov (United States)

Moreno-García, J; Coi, A L; Zara, G; García-Martínez, T; Mauricio, J C; Budroni, M

2018-03-01

Flor yeasts are Saccharomyces cerevisiae strains noted by their ability to create a type of biofilm in the air-liquid interface of some wines, known as 'flor' or 'velum', for which certain proteins play an essential role. Following a proteomic study of a flor yeast strain, we deleted the CCW14 (covalently linked cell wall protein) and YGP1 (yeast glycoprotein) genes-codifying for two cell surface glycoproteins-in a haploid flor yeast strain and we reported that both influence the weight of the biofilm as well as cell adherence (CCW14).

Thrombotic risk assessment in antiphospholipid syndrome the role of new antibody specificities and thrombin generation assay

DEFF Research Database (Denmark)

Sciascia, Savino; Baldovino, Simone; Schreiber, Karen

2016-01-01

anticoagulant, a functional coagulation assay, and anticardiolipin and anti-β2-glycoprotein-I antibodies, generally detected by solid phase enzyme-linked immunosorbent assay. The real challenge for treating physicians is understanding what is the actual weight of aPL in provoking clinical manifestations in each...

Economic evaluation of the new oral anticoagulants for the prevention of thromboembolic events: a cost-minimization analysis

Directory of Open Access Journals (Sweden)

Milena Soriano Marcolino

Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Randomized clinical trials have shown that the new oral anticoagulants have at least similar impact regarding reduction of thromboembolic events, compared with warfarin, with similar or improved safety profiles. There is little data on real costs within clinical practice. Our aim here was to perform economic analysis on these strategies from the perspective of Brazilian society and the public healthcare system. DESIGN AND SETTING: Cost-minimization analysis; anticoagulation clinic of Hospital Municipal Odilon Behrens, Belo Horizonte, MG, Brazil. METHODS: Patients at the anticoagulation clinic were recruited between August and October 2011, with minimum follow-up of four weeks. Operational and non-operational costs were calculated and corrected to 2015. RESULTS: This study included 633 patients (59% women of median age 62 years (interquartile range 49-73. The mean length of follow-up was 64 ± 28 days. The average cost per patient per month was $ 54.26 (US dollars. Direct costs accounted for 32.5% of the total cost. Of these, 69.5% were related to healthcare professionals. With regards to indirect costs, 52.4% were related to absence from work and 47.6% to transportation. Apixaban, dabigatran and rivaroxaban were being sold to Brazilian public institutions, on average, for $ 49.87, $ 51.40 and $ 52.16 per patient per month, respectively, which was lower than the costs relating to warfarin treatment. CONCLUSION: In the Brazilian context, from the perspective of society and the public healthcare system, the cumulative costs per patient using warfarin with follow-up in anticoagulation clinics is currently higher than the strategy of prescribing the new oral anticoagulants.

Traumatic events involving elderly patients treated with anticoagulants for atrial fibrillation: the downside of stroke prevention

Directory of Open Access Journals (Sweden)

Alessandro Riccardi

2016-08-01

Full Text Available A group of oral anticoagulant-treated patients affected by permanent atrial fibrillation was evaluated after their access to the emergency room as a result of a traumatic accident. In these patients, the re-evaluation of their risk of thromboembolism and bleeding was performed together with the evaluation of their risk of falling and institutionalization. Results show that the emergency department identifies a cohort of very elderly frail patients, who should be carefully reconsidered for anticoagulant therapy after a traumatic event.

Anticoagulant Activity and Structural Characterization of Polysaccharide from Abalone (Haliotis discus hannai Ino Gonad

Directory of Open Access Journals (Sweden)

Jun Zhao

2016-06-01

Full Text Available In this study, we aimed at characterizing the structure and the anticoagulant activity of a polysaccharide fraction (AGP33 isolated from the gonads of Haliotis discus hannai Ino. AGP33 was extracted by enzymatic hydrolysis and purified by ion-exchange and gel-filtration chromatography. The backbone fraction of AGP33 (BAGP33, which appeared to contain of mannose, glucose and galactose, was prepared by partial acid hydrolysis. According to methylation and nuclear magnetic resonance (NMR spectroscopy, the backbone of AGP33 was identified as mainly consisting of 1→3-linked, 1→4-linked, and 1→6-linked monosaccharides. AGP33 is a sulfated polysaccharide with sulfates occur at 3-O- and 4-O-positions. It prolonged thromboplastin time (APTT, thrombin time (TT and prothrombin time (PT compared to a saline control solution in a dosage-dependent manner. AGP33 exhibited an extension (p < 0.01 of APTT compared to the saline group at concentrations higher than 5 μg/mL. AGP33 exhibited higher anticoagulant activity than its desulfated product (AGP33-des and BAGP33. The results showed that polysaccharide with higher molecular weight and sulfate content demonstrated greater anticoagulant activity.

The effect of P-glycoprotein on methadone hydrochloride flux in equine intestinal mucosa.

Science.gov (United States)

Linardi, R L; Stokes, A M; Andrews, F M

2013-02-01

Methadone is an effective analgesic opioid that may have a place for the treatment of pain in horses. However, its absorption seems to be impaired by the presence of a transmembrane protein, P-glycoprotein, present in different tissues including the small intestine in other species. This study aims to determine the effect of the P-glycoprotein on methadone flux in the equine intestinal mucosa, as an indicator of in vivo drug absorption. Jejunum tissues from five horses were placed into the Ussing chambers and exposed to methadone solution in the presence or absence of Rhodamine 123 or verapamil. Electrical measurements demonstrated tissue viability for 120 min, and the flux of methadone across the jejunal membrane (mucosal to submucosal direction) was calculated based on the relative drug concentration measured by ELISA. The flux of methadone was significantly higher only in the presence of verapamil. P-glycoprotein was immunolocalized in the apical membrane of the jejunal epithelial cells (enterocytes), mainly located in the tip of the villi compared to cells of the crypts. P-glycoprotein is present in the equine jejunum and may possibly mediate the intestinal transport of methadone. This study suggests that P-glycoprotein may play a role in the poor intestinal absorption of methadone in vivo. © 2012 Blackwell Publishing Ltd.

[Pregnancy-specific beta-glycoprotein in the serum of women with a complicated early pregnancy].

Science.gov (United States)

Radikov, N

1989-01-01

The author determined pregnancy specific beta 1-glycoprotein in 109 women with threatened early pregnancy as 32 of the women suffered from abortus imminens with several unsuccessful pregnancies in the past as well as 67 women with abortus incipiens with bleeding ex utero. The author established that 87% of women with abortus imminens and preserved pregnancies had values of beta 1-glycoprotein close to those of normal pregnancy for the respective gestational week. 93% of women with abortus incipiens preserved pregnancies till term, but the specific glycoprotein was with in normal ranges. Spontaneous abortion occurred in 7% of women with low values under the 10th percentile. The present study show that examination of pregnancy specific beta 1-glycoprotein in women with threatened early pregnancy is of prognostic significance for the outcome of pregnancy.

Study on the extraction and purification of glycoprotein from the yellow seahorse, Hippocampus kuda Bleeker

Science.gov (United States)

Su, Yuting; Xu, Yongjian

2015-01-01

The optimum parameters of extraction for glycoprotein from seahorse were examined and determined by Box-Behnken combined with ultrasonic extraction technology. Column chromatography of glycoprotein was used for further purification. The optimal extraction conditions of seahorse glycoprotein were extracting time 4.3 h, salt concentration 0.08 mol/L, extracting temperature 73°C, raw material, and water ratio 1:6. At the optimal conditions, the yield of saccharide reached to 1.123%, and the yield of protein reached to 5.898%. For purifying the crude glycoprotein, the stage renounces of DEAE-52 column chromatography were done, respectively, with 0.05, 0.1, 0.5 mol/L NaHCO3 solution, and further purification was done with Sephadex G-100 column chromatography. Finally, two pieces of seahorse glycoprotein were obtained by the column chromatography, that is, HG-11 and HG-21. The saccharide content was 56.7975% and 39.479%, the protein content was 30.5475% and 51.747%, respectively. PMID:26288722

Improved radioimmunoassay for urinary Tamm-Horsfall glycoprotein. Investigation and resolution of factors affecting its quantification

Energy Technology Data Exchange (ETDEWEB)

Dawney, A B.St.J.; Thornley, C; Cattell, W R [Saint Bartholomew' s Hospital, London (UK)

1982-09-15

A rapid specific radioimmunoassay has been used to measure Tamm-Horsfall glycoprotein (TH glycoprotein) in urine, and the method described. The apparent concentration increased with increasing dilution of urine in water, reaching a plateau at 1 in 20. This increase was greater the higher the osmolality and TH glycoprotein concentration and the lower the pH of the original sample. The apparent concentration of TH glycoprotein in neat or diluted urine was not affected by freezing or by storage at 4/sup 0/C or room temperature for at least 2 days. A physiological range for the urinary excretion rate was established as 22-56 mg/24h, (considerably higher than the amount present in serum) based on samples from 29 individuals with normal renal function, as defined by their creatinine clearance. There was no significant correlation between serum concentrations of TH glycoprotein and its urinary excretion rate, nor between urinary excretion rate and creatinine clearance.

CD150 is a member of a family of genes that encode glycoproteins on the surface of hematopoietic cells.

Science.gov (United States)

Wang, N; Morra, M; Wu, C; Gullo, C; Howie, D; Coyle, T; Engel, P; Terhorst, C

2001-07-01

Human CD150 (SLAM) is a glycoprotein expressed on the surface of T, B, natural killer, and dendritic cells. The extracellular domain of CD150 is the receptor for measles virus and CD150 acts as a co-activator on T and B cells. We characterized the mouse and human CD150 genes, each of which comprises seven exons spanning approximately 32 kb. Mouse CD150 mRNA was detected in T cells and in most thymocyte subsets, except CD4-8- cells. Surprisingly, the CD4-8- thymocytes of CD3gammadeltanull mice, but not of Ragnull or severe combined immunodeficiency mice, expressed CD150. Whereas high levels of CD150 were found in Th1 cells, only small amounts were detectable in Th2 cells. CD150 expression was up-regulated upon in vitro activation of mouse T cells by anti-CD3. The complete mouse CD150 gene is highly homologous to its human orthologue in terms of nucleotide sequences and intron/exon organization. The human genomic sequences indicate that all isoforms detected so far have arisen from alternative splicing events. As judged by fluorescence in situ hybridization, mouse CD150 mapped to Chromosome (Chr) 1, band 1H2.2-2.3, and human CD150 was found on Chr 1q22. Human and mouse CD150 share sequence homologies with six other genes, five of which - CD84, CD229 (Ly-9), CD244 (2B4), CD48, and 19A - are localized in a 250-kb segment in close proximity to the human gene. Their location and their sequence similarities strongly suggest that the CD150 family of cell surface receptors arose via successive duplications of a common ancestral gene.

A novel PET imaging protocol identifies seizure-induced regional overactivity of P-glycoprotein at the blood-brain barrier

Science.gov (United States)

Bankstahl, Jens P.; Bankstahl, Marion; Kuntner, Claudia; Stanek, Johann; Wanek, Thomas; Meier, Martin; Ding, Xiao-Qi; Müller, Markus; Langer, Oliver; Löscher, Wolfgang

2013-01-01

About one third of epilepsy patients are pharmacoresistant. Overexpression of P-glycoprotein and other multidrug transporters at the blood-brain barrier is thought to play an important role in drug-refractory epilepsy. Thus, quantification of regionally different P-glycoprotein activity in the brain in vivo is essential to identify P-glycoprotein overactivity as the relevant mechanism for drug-resistance in an individual patient. Using the radiolabeled P-glycoprotein substrate (R)-[11C]verapamil and different doses of co-administered tariquidar, which is an inhibitor of P-glycoprotein, we evaluated whether small-animal positron emission tomography (PET) can quantify regional changes in transporter function in the rat brain at baseline and 48 h after a pilocarpine-induced status epilepticus. P-glycoprotein expression was additionally quantified by immunohistochemistry. To reveal putative seizure-induced changes in blood-brain barrier integrity, we performed gadolinium-enhanced magnetic resonance scans on a 7.0 Tesla small-animal scanner. Before P-glycoprotein modulation, brain uptake of (R)-[11C]verapamil was low in all regions investigated in control and post-status epilepticus rats. After administration of 3 mg/kg tariquidar, which inhibits P-glycoprotein only partially, we observed increased regional differentiation in brain activity uptake in post-status epilepticus versus control rats, which diminished after maximal P-glycoprotein inhibition. Regional increases in the efflux rate constant k2, but not in distribution volume VT or influx rate constant K1, correlated significantly with increases in P-glycoprotein expression measured by immunohistochemistry. This imaging protocol proves to be suitable to detect seizure-induced regional changes in P-glycoprotein activity and is readily applicable to humans, with the aim to detect relevant mechanisms of pharmacoresistance in epilepsy in vivo. PMID:21677164

Aspirin or anticoagulants for treating recurrent miscarriage in women without antiphospholipid syndrome

NARCIS (Netherlands)

Kaandorp, Stef; Di Nisio, Marcello; Goddijn, Mariette; Middeldorp, Saskia

2009-01-01

Background Since hypercoagulability might result in recurrent miscarriage, anticoagulant agents could potentially increase the live-birth rate in subsequent pregnancies in women with either inherited thrombophilia or unexplained recurrent miscarriage. Objectives To evaluate the efficacy and safety