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Rahmadhani Mega - One of the best experts on this subject based on the ideXlab platform.

  • Pengaruh senyawa asam 2-(3-klorobenzoiloksi) benzoat terhadap agregasi trombosit dengan metode pengujian Thrombocyte Aggregation test dan immuno-flow cytometry pada plasma manusia
    2018
    Co-Authors: Rahmadhani Mega
    Abstract:

    Asam asetilsalisilat (AAS) merupakan obat anti inflamasi, analgesik, antipiretik dan anti-trombosit dengan menghambat aktivitas pada COX-1 dan COX-2. AAS menghambat aktivitas pada COX-1, sehingga pembentukan tromboksan A2 (TXA2) dan agregasi trombosit terhambat. Namun, penggunaan AAS dapat memberikan efek samping berupa tukak lambung dan memiliki nilai toksisitas yang tinggi, sehingga berdasarkan dari hal tersebut maka dikembangkan senyawa baru turunan salisilat yaitu asam 2-(3-klorobenzoiloksi)benzoat (3K) sebagai obat baru pengganti asam asetilsalisilat dengan aktivitas anti agregasi trombosit dan efek samping yang minimal. Oleh karena itu diperlukan pemeriksaan lebih lanjut untuk melihat adanya aktivitas agregasi trombosit dengan metode uji Thrombocyte Aggregation test dan immuno-flow cytometry secara in vitro menggunakan plasma subyek dari sisi dalam lipatan siku yang disuntikkan dengan tiga kelompok uji (replikasi tiga kali). Untuk kelompok perlakuan terbagi menjadi, kontrol negatif (HEPES 50 mM), kontrol positif (asam asetilsalisilat), senyawa uji (asam 2-(3-klorobenzoiloksi). Kontrol positif dan 3K menggunakan konsentrasi 50 µg/mL (277 µmol/L). Kemudian dilakukan uji Thrombocyte Aggregation test dan uji immuno-flow cytometry meliputi uji reaktivitas antibodi pada trombosit dan uji anti agregasi trombosit. Uji immuno-flow cytometry menggunakan antibodi alexa fluor 488 anti-human AP-3 dan antibodi PE anti-human AP-3 dengan penambahan agonis berupa kolagen. Hasil uji dari 3K dibandingkan dengan kontrol negatif pada metode Thrombocyte Aggregation test adalah (0,367±0,0617 vs 0,329±0,0803 %/detik). Hasil uji immuno-flow cytometry adalah (17,02%±1,44 vs 15,12%±0,72%). Simpulan yang di peroleh bahwa pemberian senyawa asam 2-(3-klorobenzoiloksi)benzoat kurang berpotensi sebagai anti agregasi trombosit

Pudur Jagadeeswaran - One of the best experts on this subject based on the ideXlab platform.

  • g protein coupled receptor gpr34l mutation affects Thrombocyte function in zebrafish
    British Journal of Haematology, 2018
    Co-Authors: Abdullah Alsrhani, Gauri Khandekar, Lala Zafreen, Florence L Marlow, Elliott W Abrams, Mary C. Mullins, Pudur Jagadeeswaran
    Abstract:

    : Haemostasis is a defence mechanism that has evolved to protect organisms from losing their circulating fluid. We have previously introduced zebrafish as a model to study the genetics of haemostasis to identify novel genes that play a role in haemostasis. Here, we identify a zebrafish mutant that showed prolonged time to occlusion (TTO) in the laser injury venous thrombosis assay. By linkage analysis and fine mapping, we found a mutation in the orphan G protein-coupled receptor 34 like gene (gpr34l) causing a change of Val to Glu in the third external loop of Gpr34l. We have shown that injection of zebrafish gpr34l RNA rescues the prolonged TTO defect. The Thrombocytes from the mutant showed elevated levels of cAMP that supports the defective Thrombocyte function. We also have demonstrated that knockdown of this gene by intravenous Vivo-Morpholino injections yielded a phenotype similar to the gpr34l mutation. These results suggest that the lack of functional Gpr34l leads to increased cAMP levels that result in defective Thrombocyte Aggregation.

  • Intraflagellar transport proteins are involved in Thrombocyte filopodia formation and secretion
    2017
    Co-Authors: Uvaraj Radhakrishnan, Abdullah Alsrhani, Hemalatha Sundaramoorthi, Jannon L Fuchs, Gauri Khandekar, Brian D. Perkins, Yoshihiro Omori, Meghana Kashyap, Pudur Jagadeeswaran
    Abstract:

    Intraflagellar transport (IFT) proteins are vital for the genesis and maintenance of cilia. Our identification of ift122 transcripts in zebrafish Thrombocytes that lack primary cilia was unexpected. IFT proteins serve transport in cilia, whose narrow dimensions may have necessitated the evolution of IFT from vesicular transport in ancestral eukaryotes. We hypothesized that IFTs might also facilitate transport within the filopodia that form when Thrombocytes are activated. To test this possibility, we knocked down ift122 expression by injecting antisense Morpholino oligonucleotides (MOs) into zebrafish embryos. Laser-induced arterial thrombosis showed prolonged time to occlusion (TTO) of the vessel, as would be expected with defective Thrombocyte function. Acute effects in adult zebrafish were evaluated by Vivo-Morpholino (Vivo-MO) knockdown of ift122. Vivo-MO morphants showed a prolonged time to Thrombocyte Aggregation (TTA) in the plate tilt assay after Thrombocyte activation by the following agonists: ADP, collagen, PAR1 peptide, and epinephrine. A luminescence assay for ATP revealed that ATP secretion by Thrombocytes was reduced in collagen-activated blood of Vivo-MO ift122 morphants. Moreover, DiI-C18 labeled morphant Thrombocytes exposed to collagen showed reductions in filopodia number and length. Analysis of ift mutants, in which cilia defects have been noted, also showed prolongation of TTO in our arterial laser thrombosis assay. Additionally, collagen activation of wild-type Thrombocytes led to a concentration of IFT122 both within and at the base of filopodia. Taken together these results, suggest that IFT proteins are involved in both the extension of filopodia and secretion of ATP, which are critical in Thrombocyte function.

  • dioxin induced Thrombocyte Aggregation in zebrafish
    Blood Cells Molecules and Diseases, 2015
    Co-Authors: Hemalatha Sundaramoorthi, Pudur Jagadeeswaran
    Abstract:

    Abstract 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a canonical member of a group of dioxins which are byproducts of industrial combustion and are dangerous environmental pollutants. TCDD has been shown to cause several abnormalities in humans and wildlife, and recently, some dioxins have been found to activate platelets. However, TCDD-mediated platelet activation pathways are elusive and virtually nothing is known about TCDD activation of fish Thrombocytes. To investigate TCDD effect on Thrombocyte function, we tested zebrafish blood in presence of TCDD using a Thrombocyte functional assay. We found that TCDD activated Thrombocytes. Further experiments showed that Thrombocytes of fish treated with TCDD formed both aggregates and filopodia. To investigate the mechanism of TCDD-mediated activation of Thrombocytes we used inhibitors for Gq, cyclooxygenase-1, aryl hydrocarbon receptor (AHR), c-src, Akt, and ERK1/2. We found that TCDD induces AHR which activates c-src and signals the activation of Akt and ERK1/2 which are ultimately involved in generation of thromboxane A2. Furthermore, we found that ADP potentiates TCDD action, which led to the discovery that ADP itself activates AHR in the absence of TCDD. Taken together, these results resolved the pathway of TCDD activation of Thrombocytes and led to the finding that ADP is an activator of AHR.

Jarra, Febrina Fatkiyah - One of the best experts on this subject based on the ideXlab platform.

  • Pengaruh senyawa asam 2-(4-klormetilbenzoiloksi) benzoat terhadap agregasi trombosit dengan metode pengujian Thrombocyte Aggregation test dan immuno-flow cytometry pada plasma manusia
    2018
    Co-Authors: Jarra, Febrina Fatkiyah
    Abstract:

    Asam asetilsalisilat merupakan obat populer analgesik dan anti-trombosit yang sering diminum secara per-oral. Penelitian ini bertujuan untuk melakukan uji agregasi trombosit terhadap asam 2-(4-klorometilbenzoiloksi)benzoat menggunakan plasma manusia dengan metode Thrombocyte Aggregation test (TAT) dan Immuno-flow cytometry. Diharapkan data yang diperoleh dapat digunakan untuk pengembangan senyawa baru yang lebih efektif dan kurang toksik jika dibandingkan dengan aspirin. Pada penelitian ini menggunakan plasma manusia melalui lengan pasien yang diberikan beberapa perlakuan secara in vitro yaitu kelompok kontrol negatif (Hepes 50 mM), kontrol positif (Asam asetilsalisilat+Hepes 50 mM) dan senyawa uji (asam 2-(4-klorometilbenzoiloksi)benzoat+Hepes 50 mM). Pada metode ini menggunakan konsentrasi sebesar 50µg/ml (277 µM). Perlakuan menggunakan PRP yang nantinya diberi beberapa perlakuan. Pada Immuno-Flow Cytometry meliputi uji reaktivitas dan uji agregasi trombosit. Uji immuno-flow cytometry menggunakan antibodi PE anti human AP-3 dan Alexa Flour 488 anti human AP-3. Pada kedua metode uji agregasi trombosit ditambahkan agonis berupa kolagen. Hasil uji TAT diperoleh rata-rata (vmax) pada kelompok kontrol negatif adalah (0.367±0.061% detik), kontrol positif (0.179±0.062% detik) dan senyawa uji (Asam 2-(4-(klorometil)benzoiloksi)benzoat dan Hepes 50 mM) (0.311±0.031% detik). Hasil uji Immuno-Flow Cytometry diperoleh rata-rata %total (Upper Right) pada kontrol negatif (16.18 ± 1.07%), kontrol positif (10.57 ± 2.13%) dan senyawa uji 4KM (17.02 ± 1.44%). Simpulan yang dapat diperoleh pemberian senyawa asam 2-(4-klorometilbenzoiloksi)benzoat kurang berpotensi sebagai anti agregasi trombosit

Vliet, J.a. Van Der - One of the best experts on this subject based on the ideXlab platform.

  • Assessment of prosthetic vascular graft thrombogenicity using the technetium-99m labeled glycoprotein IIb/IIIa receptor antagonist DMP444 in a dog model.
    'Elsevier BV', 2002
    Co-Authors: Scharn D.m., Oyen W.j.g., Klemm P.l., Wijnen M.h.w.a., Vliet, J.a. Van Der
    Abstract:

    Item does not contain fulltextINTRODUCTION: Prosthetic graft patency greatly depends on graft thrombogenicity. The concept of graft thrombogenicity is poorly understood and difficult to measure or quantify. In a study we tested the experimental radiopharmaceutical DMP444 and developed a suitable dog model. This agent is a radiolabelled ((99m)Technetium) glycoprotein IIb/IIIa receptor antagonist with a high affinity for activated platelets. It binds to platelets that are intimately involved in thrombus formation. The agent does not affect Thrombocyte function, when used in a dose necessary for imaging. DMP444 does not require platelet harvesting and processing. Early imaging of Thrombocyte Aggregation sites such as vascular prostheses is possible within 4 hours after injection. MATERIAL AND METHODS: Adult Beagle dogs weighing 12-15 kg were used for the experiments. In 16 dogs a prosthetic patch was sewn onto the abdominal aorta (Bovine pericard: n=4, Dacron: n=6, Human Umbilical Vein: n=6). Imaging cycles after injection of (99m)Technetium-labelled DMP444 were performed on days 1, 7, 14 and 28 after surgery. RESULTS: We noticed differences in thrombus formation on the tested graft materials. The bovine pericard patches (n=4) showed a relatively high rate of Thrombocyte Aggregation. In the Dacron patches (n=6) Aggregation was not seen. In 1 of 6 cases of human umbilical vein patches a measurable focal Aggregation was recorded. CONCLUSION: The method outlined in this study is a relatively simple and reproducable method to visualize Thrombocyte Aggregation

  • Assessment of prosthetic vascular graft thrombogenicity using the technetium-99m labeled glycoprotein IIb/IIIa receptor antagonist DMP444 in a dog model.
    2002
    Co-Authors: Scharn D.m., Oyen W.j.g., Klemm P.l., Wijnen M.h.w.a., Vliet, J.a. Van Der
    Abstract:

    INTRODUCTION: Prosthetic graft patency greatly depends on graft thrombogenicity. The concept of graft thrombogenicity is poorly understood and difficult to measure or quantify. In a study we tested the experimental radiopharmaceutical DMP444 and developed a suitable dog model. This agent is a radiolabelled ((99m)Technetium) glycoprotein IIb/IIIa receptor antagonist with a high affinity for activated platelets. It binds to platelets that are intimately involved in thrombus formation. The agent does not affect Thrombocyte function, when used in a dose necessary for imaging. DMP444 does not require platelet harvesting and processing. Early imaging of Thrombocyte Aggregation sites such as vascular prostheses is possible within 4 hours after injection. MATERIAL AND METHODS: Adult Beagle dogs weighing 12-15 kg were used for the experiments. In 16 dogs a prosthetic patch was sewn onto the abdominal aorta (Bovine pericard: n=4, Dacron: n=6, Human Umbilical Vein: n=6). Imaging cycles after injection of (99m)Technetium-labelled DMP444 were performed on days 1, 7, 14 and 28 after surgery. RESULTS: We noticed differences in thrombus formation on the tested graft materials. The bovine pericard patches (n=4) showed a relatively high rate of Thrombocyte Aggregation. In the Dacron patches (n=6) Aggregation was not seen. In 1 of 6 cases of human umbilical vein patches a measurable focal Aggregation was recorded. CONCLUSION: The method outlined in this study is a relatively simple and reproducable method to visualize Thrombocyte Aggregation

Gary Violetta - One of the best experts on this subject based on the ideXlab platform.

  • comparison of sea turtle Thrombocyte Aggregation to human platelet Aggregation in whole blood
    Comparative Biochemistry and Physiology B, 2005
    Co-Authors: Gerald Soslau, Peggy Jean Prest, Reiner Class, Robert H George, Frank V Paladino, Gary Violetta
    Abstract:

    : The endangered sea turtles are living "fossils" that afford us an opportunity to study the hemostatic process as it likely existed millions of years ago. There are essentially no data about turtle Thrombocyte Aggregation prior to our studies. Thrombocytes are nucleated cells that serve the same hemostatic functions as the anucleated mammalian platelet. Sea turtle Thrombocytes aggregate in response to collagen and beta-thrombin. Ristocetin induces an agglutination/Aggregation response indicating the presence of a von Willebrand-like receptor, GPIb, found in all mammalian platelets. Samples treated with alpha-thrombin plus gamma-thrombin followed by ristocetin results in a rapid, stronger response than ristocetin alone. These responses are inhibited by the RGDS peptide that blocks fibrinogen cross-linking of mammalian platelets via the fibrinogen receptor, GPIIb/IIIa. Three platelet-like proteins, GPIb, GPIIb/IIIa and P-selection are detected in sea turtle Thrombocytes by fluorescence activated cell sorting. Turtle Thrombocytes do not respond to ADP, epinephrine, serotonin, thromboxane A2 mimetic, U46619, trypsin, or alpha-thrombin and gamma-thrombin added alone. Comparison of hemostasis in sea turtles to other vertebrates could provide a framework for understanding the structure/function and evolution of these pathways and their individual components.