The Hemostatic Effect of Ankaferd Blood Stopper in Rat Bleeding Models with Antithrombotic Drug Therapy: An Experimental <i>In Vivo</i> Study

In the interpretation of data obtained with 51Cr-labelled platelets it is vital to know whether they are functionally normal. Although survival of 51Cr-labelled platelets in vivo appears to be normal, platelet aggregability- has recently been shown to be reduced after the labelling procedure (Björnson, J., Sc and. J. Haemat. 13, 252–259).The aim of the present study was to examine the hemostatic effect of labelled platelets. Rabbits were made thrombocytopenic (< 35,000/μ1) by whole body irradiation. Bleeding times were recorded after standardized cuts on the inner side of the ear, a method showing an acceptable reproducibility (< 3 min in normals). The animals were then transfused with labelled platelet concentrates, increasing the platelet levels to about 200,000/μ) blood. Bleeding times of more than 15 min before transfusion were almost normalized 1 and 4 hours after transfusion. In controls transfusion of PRP led to similar shortening of bleeing time.It is concluded that platelets subjected to the 51Cr-labelling procedure to a large extent retain their hemostatic ability.

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Improved hemostasis with superactive analogs of factor VIIa in a mouse model of hemophilia A

Blood ◽

10.1182/blood-2003-05-1369 ◽

2003 ◽

Vol 102 (10) ◽

pp. 3615-3620 ◽

Cited By ~ 82

Author(s):

Mikael Tranholm ◽

Kim Kristensen ◽

Annemarie T. Kristensen ◽

Charles Pyke ◽

Rasmus Røjkjær ◽

...

Keyword(s):

Blood Loss ◽

Bleeding Time ◽

Hemophilia A ◽

Recombinant Factor Viia ◽

Factor Viia ◽

Intrinsic Activity ◽

Hemostatic Effect ◽

Therapeutic Doses ◽

Hemostatic Effects

AbstractIt is currently debated whether the mechanism of action of therapeutic doses of recombinant factor VIIa (rFVIIa, Novo-Seven) relies on the tissue factor (TF)-independent activity of the enzyme. The present study was conducted to investigate the in vivo hemostatic effects of rFVIIa and 3 analogs thereof with superior intrinsic activity (FVIIaIIa, K337A-FVIIaIia, and M298Q-FVIIa) in mice with antibody-induced hemophilia A. A highly significant dose response was observed for the bleeding time and blood loss for each of the rFVIIa variants. The bleeding time and blood loss were normalized after administration of 10 mg/kg rFVIIa, 3 mg/kg K337A-FVIIaIia, and 3 mg/kg M298Q-FVIIa, indicating a potency of these FVIIa analogs 3-4 times above that of rFVIIa in FVIII-depleted mice. The different in vivo potencies of the various forms of FVIIa could not be explained by the pharmacokinetics. Histopathological evaluation of kidneys revealed no signs of treatment-related pathological changes even after treatment with the superactive variants. The fact that FVIIa analogs with enhanced intrinsic activity are more efficacious in the murine hemophilia A model strongly suggests that the TF-independent procoagulant activity of FVIIa contributes to its clinical hemostatic effect. (Blood. 2003; 102:3615-3620)

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Systemic hemostatic and hemostasiological effects of fibrin monomer in low dose under warfarin action in experiment

Тромбоз, гемостаз и реология ◽

10.25555/thr.2019.3.0885 ◽

2019 ◽

Author(s):

В.М. Вдовин ◽

А.П. Момот ◽

Д.А. Орехов ◽

И.Г. Толстокоров ◽

В.О. Шевченко ◽

...

Keyword(s):

Liver Injury ◽

Blood Loss ◽

Prothrombin Complex Concentrate ◽

Coagulation Factors ◽

International Normalized Ratio ◽

Blood Coagulation Factors ◽

Circulating Blood Volume ◽

Hemostatic Effect ◽

Blood Loss Volume

Введение. Ранее было показано, что фибринмономер (ФМ) в низких дозировках обладает системным гемостатическим действием в условиях дозированной травмы. Авторами выдвинута гипотеза, согласно которой ФМ способен оказывать регулирующее гемостатическое действие in vivo на фоне сниженного гемостатического потенциала. Цель исследования: изучение системных гемостатических и гемостазиологических эффектов ФМ на фоне дозированной травмы печени при гипокоагуляции, обусловленной приемом варфарина. Материалы и методы. В работе использовали 40 кроликов породы Шиншилла. Для индукции кумаринобусловленной гипокоагуляции животным per os вводили варфарин в дозе 0,4 0,5 мг/кг 14 дней до достижения международного нормализованного отношения (МНО) более 2,0. Далее животным в краевую вену уха вводили концентрат факторов протромбино вого комплекса (КФПК) в дозе 40 ЕД/кг, ФМ в дозе 0,25 мг/кг или плацебо. Через 1 ч после введения препаратов наносили травму печени и оценивали кровопотерю (в процентах от объема циркулирующей крови). Исследовали число тромбоцитов, активированное парциальное тромбопластиновое время, МНО, содержание фибриногена и Ддимера, оценивали результаты тромбоэластографии крови. Результаты. Объем кровопотери в группах животных после внутривенного введения ФМ и КФПК на фоне приема варфарина был в 9,1 раза и 6,7 раза меньше, соответственно, по сравнению с группой плацебо, получавшей тот же антикоагулянт. Вместе с тем ФМ не влиял на параметры коагулограммы (отсутствие видимого гемостазиологического эффекта) и тромбоэластограммы, тогда как применение КФПК в качестве антидота варфарина сопровождалось нормализацией параметров тромбоэластометрии и коррекцией гипокоагуляционного сдвига по МНО. Заключение. Установлено, что ФМ способен проявлять свое системное гемостатическое действие в условиях сниженного тромбинообразования, обусловленного нарушением синтеза витамин Кзависимых факторов свертывания крови. Данное действие реализуется без признаков восстановления гемостатического равновесия. Introduction. It was shown earlier that fibrinmonomer (FM) in low doses had a systemic hemostatic effect in a controlled injury condition. The authors suggest that FM is able to exert a regulating hemostatic effect in vivo under reduced hemostatic potential. Aim: to study the systemic hemostatic and hemostasiological effects of FM under controlled liver injury during hypocoagulation caused by warfarin administration. Materials and methods. In this study 40 Chinchilla rabbits were used. For the induction of coumarinmediated hypocoagulation, animals were administered per os warfarin at a dose of 0.4 0.5 mg/kg for 14 days, until an international normalized ratio (INR) was more than 2.0. Subsequently, a prothrombin complex concentrate (PCC) at a dose of 40 U/kg, FM at a dose of 0.25 mg/kg or placebo were administered into the marginal ear vein of the animals. An hour later, a liver injury was inflicted and blood loss was assessed (in percents of the circulating blood volume). The number of platelets, activated partial thromboplastin time, INR, levels of fibrinogen and Ddimer were studied and the results of blood thromboelastography were evaluated. Results. Blood loss volume in animals groups after intravenous administration of FM and PPC, under warfarin reception, was 9.1 times and 6.7 times less, respectively, compared to the placebo group receiving the same anticoagulant. However, FM did not affect on coagulogram parameters (no visible hemostasiological effect) and thromboelastogram, whereas the use of PPC as warfarin antidote was accompanied by the normalization of thromboelastometry parameters and hypocoagulation shift correction according to INR. Conclusion. It was found that FM able to manifest its systemic hemostatic effect in conditions of reduced thrombin formation caused by impaired synthesis of vitamin Kdependent blood coagulation factors. This effect is implemented without any signs of recovery of hemostatic balance.

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A Review on Application of Novel Solid Nanostructures in Drug Delivery

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.53.22 ◽

2018 ◽

Vol 53 ◽

pp. 22-36 ◽

Cited By ~ 4

Author(s):

Habibollah Faraji ◽

Reza Nedaeinia ◽

Esmaeil Nourmohammadi ◽

Bizan Malaekeh-Nikouei ◽

Hamid Reza Sadeghnia ◽

...

Keyword(s):

Drug Delivery ◽

Drug Therapy ◽

Biomedical Applications ◽

Imaging Biomarkers ◽

Cellular Functions ◽

Scientific Innovation ◽

Wide Range ◽

Targeted Drug

Nanotechnology as a multidisciplinary and scientific innovation plays an important role in numerous biomedical applications, such as molecular imaging, biomarkers and biosensors and also drug delivery. A wide range of studies have been conducted on using of nanoparticles for early diagnosis and targeted drug therapy of various diseases. In fact, the small size, customized surface, upgraded solubility, or multi-functionality of nanoparticles enabled them to interact with complex cellular functions in new ways which opened many doors and created new biomedical applications. These studies demonstrated that nanotechnology vehicles can formulate biological products effectively, and this nano-formulated products with a potent ability against different diseases, were represented to have better biocompatibility, bioaccessibility and efficacy, under in vitro and in vivo conditions.

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Factor VIIa induces extracellular vesicles from the endothelium: A potential mechanism for its hemostatic effect

Blood ◽

10.1182/blood.2020008417 ◽

2021 ◽

Author(s):

Kaushik Das ◽

Shiva Keshava ◽

Shabbir A Ansari ◽

Vijay Kumar Reddy Kondreddy ◽

Charles Esmon ◽

...

Keyword(s):

Endothelial Cells ◽

Extracellular Vesicles ◽

Factor Viia ◽

Mutant Mice ◽

In Vivo Studies ◽

Cell Protein ◽

Wild Type ◽

Hemostatic Effect

Recombinant FVIIa (rFVIIa) is used as a hemostatic agent to treat bleeding disorders in hemophilia patients with inhibitors and other groups of patients. Our recent studies showed that FVIIa binds endothelial cell protein C receptor (EPCR) and induces protease-activated receptor 1 (PAR1)-mediated biased signaling. The importance of FVIIa-EPCR-PAR1-mediated signaling in hemostasis is unknown. In the present study, we show that FVIIa induces the release of extracellular vesicles (EVs) from endothelial cells both in vitro and in vivo. Silencing of EPCR or PAR1 in endothelial cells blocked the FVIIa-induced generation of EVs. Consistent with these data, FVIIa treatment enhanced the release of EVs from murine brain endothelial cells isolated from wild-type, EPCR overexpressors, and PAR1-R46Q mutant mice, but not EPCR-deficient or PAR1-R41Q mutant mice. In vivo studies revealed that administration of FVIIa to wild-type, EPCR overexpressors, and PAR1-R46Q mutant mice, but not EPCR-deficient or PAR1-R41Q mutant mice, increase the number of circulating EVs. EVs released in response to FVIIa treatment exhibit enhanced procoagulant activity. Infusion of FVIIa-generated EVs and not control EVs to platelet-depleted mice increased thrombin generation at the site of injury and reduced blood loss. Administration of FVIIa-generated EVs or generation of EVs endogenously by administering FVIIa augmented the hemostatic effect of FVIIa. Overall, our data reveal that FVIIa treatment, through FVIIa-EPCR-PAR1 signaling, releases EVs from the endothelium into the circulation, and these EVs contribute to the hemostatic effect of FVIIa.

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o-Raffinose cross-linked hemoglobin improves the hemostatic defect associated with anemia and thrombocytopenia in rabbits

Blood ◽

10.1182/blood.v96.10.3630 ◽

2000 ◽

Vol 96 (10) ◽

pp. 3630-3636 ◽

Cited By ~ 20

Author(s):

David H. Lee ◽

Leslie Bardossy ◽

Nichole Peterson ◽

Morris A. Blajchman

Keyword(s):

Blood Loss ◽

Bleeding Time ◽

Platelet Reactivity ◽

Inhibitory Effect ◽

Clinical Settings ◽

No Donor ◽

Hemostatic Effect ◽

Circulating Levels

Abstract Several different preparations of cross-linked hemoglobin (CLHb) are being evaluated for their efficacy and safety as red cell substitutes in a variety of preclinical and clinical settings. Because CLHb is known to sequester nitric oxide (NO) and inhibit NO-mediated processes, we hypothesized that CLHb would have a hemostatic effect by enhancing platelet reactivity, inducing vasoconstriction, or both. Infusion of o-raffinose CLHb shortened the prolonged microvascular bleeding time and decreased blood loss from ear incisions in rabbits rendered anemic and thrombocytopenic. Moreover, this hemostatic effect persisted for at least 24 hours after infusion. Phenylephrine induced a degree of vasoconstriction similar to that induced by CLHb but did not shorten the bleeding time or decrease blood loss, suggesting that vasoconstriction alone cannot account for the hemostatic effect of CLHb. There was no evidence of CLHb-induced activation of coagulation in vivo, since infusion of CLHb did not increase circulating levels of thrombin-antithrombin complex. In vitro, CLHb abolished the inhibitory effect of the NO donor 3-morpholinosydnonimine on platelet aggregation and enhanced the aggregation of stimulated but not resting platelets. This potentiating effect was not attenuated by the addition of superoxide dismutase or catalase. To evaluate the potential arterial thrombogenicity of CLHb, a model of carotid artery thrombosis was developed in rabbits without thrombocytopenia or anemia. Compared with albumin infusion, CLHb infusion shortened the time to complete carotid occlusion. These data suggest that CLHb may shift the thromboregulatory balance toward clot formation, resulting in decreased bleeding in anemic and thrombocytopenic rabbits and possibly increasing arterial thrombogenicity in normal rabbits.

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Clinical outcome of patients with obscure gastrointestinal bleeding during antithrombotic drug therapy

Therapeutic Advances in Gastroenterology ◽

10.1177/1756283x17746930 ◽

2018 ◽

Vol 11 ◽

pp. 1756283X1774693 ◽

Cited By ~ 3

Author(s):

Yoshiyasu Kono ◽

Seiji Kawano ◽

Yuki Okamoto ◽

Yuka Obayashi ◽

Yuki Baba ◽

...

Keyword(s):

Drug Therapy ◽

Clinical Outcome ◽

Gastrointestinal Bleeding ◽

Therapeutic Intervention ◽

Drug Users ◽

University Hospital ◽

Obscure Gastrointestinal Bleeding ◽

Antithrombotic Drug ◽

Significant Difference ◽

Rebleeding Rate

Background: The clinical outcome of patients with obscure gastrointestinal bleeding (OGIB) during antithrombotic drug therapy has not been fully investigated. Methods: Patients who underwent video capsule endoscopy (VCE) for the investigation of OGIB at Okayama University Hospital from January 2009 to March 2016 were enrolled. We evaluated the VCE findings, the patterns of OGIB, and the rate of rebleeding within 1 year in antithrombotic drug users and antithrombotic drug nonusers. Results: A total of 181 patients were enrolled. Among the antithrombotic drug users, the rate of VCE positivity in the patients with overt OGIB was significantly higher in comparison with patients with occult OGIB (45% versus 16%, p = 0.014), whereas there was no significant difference among the antithrombotic drug nonusers (27% versus 26%, p = 1.0). Among the antithrombotic drug users, the rate of rebleeding among the VCE-positive patients was significantly higher in comparison with the VCE-negative patients (50% versus 5.9%, p = 0.011). Moreover, among antithrombotic drug users who did not receive therapeutic intervention, the rate of rebleeding among the VCE-positive patients was significantly higher in comparison with the VCE-negative patients (75% versus 6.3%, p = 0.001). However, among the antithrombotic drug nonusers who did not receive therapeutic intervention, the rebleeding rate of the VCE-positive patients was not significantly different from that of the VCE-negative patients (20% versus 9.4%, p = 0.43). Conclusion: Therapeutic intervention should be considered for patients with overt OGIB who are VCE positive and who use antithrombotic drugs due to the high risk of rebleeding.

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Pharmacobiological management of hemostasis within clinical backgrounds via Ankaferd hemostat (Ankaferd blood stopper)

SAGE Open Medicine ◽

10.1177/2050312120907811 ◽

2020 ◽

Vol 8 ◽

pp. 205031212090781 ◽

Cited By ~ 1

Author(s):

Rafiye Ciftciler ◽

Ali Erdinc Ciftciler ◽

Umit Yavuz Malkan ◽

Ibrahim C Haznedaroglu

Keyword(s):

Urtica Dioica ◽

Erythrocyte Aggregation ◽

Hemostatic Agent ◽

Thymus Vulgaris ◽

Controlled Trials ◽

Hemostatic Effect ◽

Alpinia Officinarum ◽

Current Perspective ◽

Ankaferd Blood Stopper ◽

Oxidative Effects

Ankaferd hemostat (Ankaferd blood stopper [ABS], Istanbul, Turkey) is a hemostatic agent affecting red blood cell-fibrinogen interactions. ABS has been traditionally used in Anatolia as a hemostatic agent for centuries. ABS contains a standardized combination of the plants namely Glycyrrhiza glabra, Thymus vulgaris, Alpinia officinarum, Vitis vinifera, and Urtica dioica. The hemostatic effect of ABS depends upon the quick promotion of a protein network, particularly fibrinogen gamma, in relation to the erythrocyte aggregation. The aim of this review is to indicate pharmacobiological basis and clinical backgrounds of ABS. Current perspective for using ABS is to provide hemostasis and accelerating wound healing particularly in cases which are difficult to manage. Future controlled trials are needed to elucidate the actions of ABS with in hemostasis, antithrombotic, anti-inflammatory, anti-infective, antifungal, and anti-oxidative effects.

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Adoptive Transfer of CMV-Specific Donor T Cells Following Allogeneic Transplantation Leads to Rapid and Safe Systemic Reconstitution.

Blood ◽

10.1182/blood.v114.22.44.44 ◽

2009 ◽

Vol 114 (22) ◽

pp. 44-44

Author(s):

Karl S Peggs ◽

Kirsty Thomson ◽

Edward Samuel ◽

Gemma Dyer ◽

Julie Armoogum ◽

...

Keyword(s):

T Cells ◽

Drug Therapy ◽

T Cell ◽

Peripheral Blood ◽

Chronic Gvhd ◽

Antiviral Drug ◽

Donor T Cells ◽

Post Infusion ◽

Cmv Reactivation

Abstract Abstract 44 Reactivation of CMV remains a significant problem following allogeneic hematopoietic stem cell transplantation. Antiviral drug therapy is effective but toxic, and resistant strains of CMV are increasingly being reported. Virus-specific T lymphocytes are necessary for the control of viral reactivation. Adoptive transfer of donor derived CMV-specific T cells has been reported previously but most methods to produce such cells have involved several weeks of in vitro culture or have produced a therapeutic product restricted to CD8 T cells. The current method involves a short incubation of donor peripheral blood mononuclear cells with either CMV-pp65 protein (20 hours) or a pool of peptides from pp65 (6 hours) with subsequent isolation of interferon-gamma secreting cells by CliniMACS using IFNψ capture microbeads (Miltenyi Biotec). This technique permits rapid isolation of an enriched IFNψ secreting T cell product, manufactured to clinical grade, which is then cryopreserved in dosed aliquots for subsequent infusion. Here we report the outcome of a single arm phase I/II in which CMV-T cells given pre-emptively at first detection (qPCR) of CMV DNA in peripheral blood, or at day +40-60 as prophylaxis. CMV replication was monitored by weekly PCR and reconstitution of CMV-specific T cells by pentamer labelling and/or IFNψ secretion assay. Conventional antiviral drug therapy was instituted if the viral load rose above institutional threshold. 30 recipients of T cell depleted low intensity transplants from HLA-matched CMV-seropositive related donors were enrolled between 2006 and 2008. Donors underwent a second, short apheresis procedure approximately 15 days after collection of the mobilised HPC-A for the collection of CMV-T cells. 26 clinical-grade products were produced to full cGMP standards; four donors were unsuitable or withdrew. The mean yield of cells following enrichment was 41.7% with a median purity of 43.9% (range 1.4-81.8). Adequate CMV-T cells were isolated from all donors. Both pp65 and peptide stimulated products contained both CD4 and CD8 reactive T cells. Median dose of CMV-specific CD4 T cells was 2840/kg and of CMV-specific CD8 was 630/kg. Eighteen patients received a single dose of 1×10^4 CD3+/kg; 13 were CMV seropositive; 11 were treated pre-emptively and 7 prophylactically. 83% had received T cell deplete regimens. Within 2 weeks of infusion in vivo expansion of CMV-T cells was observed in 17 of 18 patients. One patient required 4 weeks to generate detectable CMV-T cell in his peripheral blood. TCR-BV usage of the CMV-T cells post infusion matched that of the cells which had been infused. The 7 patients who had cells infused prophylactically all showed expansions of CMV-T cells in the absence of detectable viral DNA in peripheral blood. Subsequent low level CMV-reactivation was seen in one of these and was associated with rapid CMV-T cell expansion with clearance of virus without anti-viral drug therapy. One developed subsequent extensive chronic GvHD and required antiviral treatment for multiple reactivation episodes following introduction of steroids. Of the 11 patients treated pre-emptively, 9 received antiviral therapy for the initial reactivation, although in 7 patients this was required for only 7-15 days. (compared to a median of 21 days in historical controls). Three patients had a further CMV reactivation event. One followed prednisolone therapy for acute grade II GvHD. The second was the patient who had shown poor T cell expansion post infusion and had required prolonged anti-viral therapy (33 days) for the initial CMV reactivation. The third patient received no treatment and cleared virus following a further in vivo expansion of CMV-reactive T cells, suggesting the presence of a functional memory population. GVHD incidence and severity was no worse than seen in comparable historical controls. 3 patients suffered grade 2-3 acute GvHD. 3/17 evaluable patients developed extensive chronic GvHD (2 were recipients of T replete grafts). 16/18 patients were alive at the end of the 6 month monitoring period and CMV-reactive T cells were detectable in all 16. CMV-specific donor T cells can be readily produced to cGMP compliance which can be safely infused and lead to early immune reconstitution in at-risk patients. Cells expand in response to subsequent CMV-reactivation and patients appear to require fewer anti-viral treatment episodes which is being tested in an ongoing phase III trial. Disclosures: Lowdell: Cell Medica Ltd: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

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