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Rushchak VV, Kovalenko VM, Voronina AK, Kitam VO, Maksymchuk OV, Chashchyn MO. [Optimization of animal model for investigation of pathogenesis of type 2 diabetes]. FIZIOLOHICHNYI ZHURNAL (KIEV, UKRAINE : 1994) 2012; 58:29-35. [PMID: 23530411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Diabetes mellitus is one of the three most common modem diseases. A number of animal models is used in investigations of the mechanisms of development of the disease. Most of these models replicate the symptoms of type 1 diabetes mellitus. The development of type 2 diabetes is caused by the insulin resistance, hyperglycemia, structural and functional disorders of the pancreatic cells. Investigation of pathogenesis of type 2 diabetes is complicated by the lack of adequate models of this disease. In this work, based on existing hyperglycemia model, we propose the model of metabolic syndrome as a precursor of type 2 diabetes. The development of metabolic syndrome symptoms was caused by 28 days long intramuscular injection of protamine sulfate to guinea pigs at a dose of 15 mg/kg along with keeping of animals on a high glucose diet. Increased blood glucose and cholesterol levels, reduction of glycogen in liver, the structural and functional damage and reduce in the number of functionally active beta-cells in the pancreas of the experimental animals were observed. The results confirm the development of the metabolic syndrome symptoms in experimental animals, which makes it possible to use such methodical approach in creation of promising type 2 diabetes model.
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Sasaki M, Horiguchi S, Chiba Y. [Influence of protamine sulfate as neutralizer of heparin on a vancomycin assay in serum]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 2011; 59:656-661. [PMID: 21874791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Levels of vancomycin (VCM), measured with cobas 6000 c501(c501), were low when blood-collecting tubes for heparinized blood (SQH) were used. It was determined that the phenomenon was due to the effects of protamine sulfate, a heparin neutralizer. VCM levels decreased by approximately 10% when the concentration of protamine sulfate was 0.01 mg/ml, and were undetectable when the concentration was 0.045 mg/ml. However, the effects of protamine sulfate, with the dose being up to approximately twice, were not seen in the presence of heparin. There were no such effects if specimens in SQH were maintained at a specified volume. The phenomenon was characteristic of the measurement of VCM levels using c501. Measurements of other agents such as valproic acid, which is measured in the same manner as VCM, using the same equipment did not lead to the identification of any effect. In addition, when VCM levels were measured with reagents of INTEGRA 800, no effect was seen. It is difficult to elucidate the mechanisms of action, as the manufacturer has not provided detailed information regarding reagents. Protamine sulfate is estimated to partially influence the antigen-antibody reaction involving anti-VCM antibodies in reagents of c501. Protamine sulfate is also used as an injection, and, hence, the influence of the agent on VCM levels measured with c501 cannot be ruled out even if other blood collecting tubes are used. Attachment to separating mediums presents problems when measuring blood concentrations of drugs, but there has been no report regarding a heparin neutralizer, as seen in this case. This is a new influential factor that requires attention.
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BIRKINSHAW VJ, SMITH KL. The Assay of Protamine Sulphate for its Capacity to Neutralise Heparin. J Pharm Pharmacol 2011; 14(Suppl):95T-96T. [PMID: 13971139 DOI: 10.1111/j.2042-7158.1962.tb10538.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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NORDOY A. Difference in the Heparin-Neutralizing Effect of Protamine and Polybrene as Tested by Thrombotest. Scandinavian Journal of Clinical and Laboratory Investigation 2010; 15:205-10. [PMID: 13938906 DOI: 10.3109/00365516309079733] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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LISNELL A, MELLGREN J. EFFECT OF HEPARIN, PROTAMINE, DICOUMAROL, STREPTOKINASE AND EPSILON-AMINO-N-CAPROIC ACID ON THE GROWTH OF HUMAN CELLS IN VITRO1. ACTA ACUST UNITED AC 2009; 57:145-53. [PMID: 13930893 DOI: 10.1111/j.1699-0463.1963.tb03439.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Lehmann V. Properties of purified phospholipase C from Acinetobacter calcoaceticus. ACTA PATHOLOGICA ET MICROBIOLOGICA SCANDINAVICA. SECTION B: MICROBIOLOGY AND IMMUNOLOGY 2009; 80:827-34. [PMID: 4630254 DOI: 10.1111/j.0365-5563.1973.tb00008.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Latallo ZS, Wegrzynowicz Z, Budzyński AZ, Kopeć M. Effect of protamine sulphate on the solubility of fibrinogen, its derivatives and other plasma proteins. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:151-62. [PMID: 5290676 DOI: 10.1111/j.1600-0609.1971.tb02001.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Godal HC, Kierulf P. Precipitation of fibrinogen-derived material by protamine. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:163-4. [PMID: 5290677 DOI: 10.1111/j.1600-0609.1971.tb02002.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Cash JD, Fuster V, Clarkson AR. Preliminary studies on the protamine sulphate precipitation of plasma and serum. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:179-81. [PMID: 5290678 DOI: 10.1111/j.1600-0609.1971.tb02004.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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61
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Bouma BN. The results of a comparison of the tanned red cell hemagglutination inhibition immuno-assay with an immunochemical method for the determination of splitproducts. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:111-4. [PMID: 4258197 DOI: 10.1111/j.1600-0609.1971.tb01995.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Musumeci V. Ethanol gelation test and protamine sulphate test in diagnosis of intravascular coagulation. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:197-202. [PMID: 5290682 DOI: 10.1111/j.1600-0609.1971.tb02008.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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63
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Latallo ZS, Wegrzynowicz Z, Kopeć M. Preparation of soluble fibrin complexes in plasma. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:385. [PMID: 5290698 DOI: 10.1111/j.1600-0609.1971.tb02041.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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64
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Latallo ZS, Teisseyre E. Practical method for separation of the active component from a mixture of early fibrinogen degradation products. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:383-4. [PMID: 4258206 DOI: 10.1111/j.1600-0609.1971.tb02040.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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65
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Latallo ZS, Wegrzynowicz Z, Teisseyre E, Kopeć M. Simple and rapid evaluation of the intravascular coagulation and fibrinolytic states by application of protamine sulphate and reptilase R. SCANDINAVIAN JOURNAL OF HAEMATOLOGY. SUPPLEMENTUM 2009; 13:387-8. [PMID: 5290699 DOI: 10.1111/j.1600-0609.1971.tb02042.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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66
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Bauer K. Protamines, histones and the genetic code. New evidence for code evaluations. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 2009; 8:13-9. [PMID: 1248921 DOI: 10.1111/j.1399-3011.1976.tb02475.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A new approach is presented to give evidence for the theories of Jukes and Crick (1-3) that at a more primitive stage the genetic code consisted of doublets separated by "comma-bases" rather than true triplets and that G and C or A and U are the exclusive bases used by the primordial code. This approach makes use of the conservation of the histone IV sequence over extremely long periods of time by comparing the amino acid composition of the average vertebrate protein with the one of histone IV, a reconstructed ancestral polypeptide and various nuclear proteins, homologous or otherwise related to it. All protamines studied and the majority of histones show deviations from the average vertebrate protein which are statistically highly significant if the amino acids sufficiently coded for by the first two bases are compared. A similar result is obtained for those amino acids which are sufficiently coded for by the first two bases of the codon and have codons composed of G and C only.
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Peer D, Park EJ, Morishita Y, Carman CV, Shimaoka M. Systemic leukocyte-directed siRNA delivery revealing cyclin D1 as an anti-inflammatory target. Science 2008; 319:627-30. [PMID: 18239128 PMCID: PMC2490797 DOI: 10.1126/science.1149859] [Citation(s) in RCA: 381] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cyclin D1 (CyD1) is a pivotal cell cycle-regulatory molecule and a well-studied therapeutic target for cancer. Although CyD1 is also strongly up-regulated at sites of inflammation, its exact roles in this context remain uncharacterized. To address this question, we developed a strategy for selectively silencing CyD1 in leukocytes in vivo. Targeted stabilized nanoparticles (tsNPs) were loaded with CyD1-small interfering RNA (siRNA). Antibodies to beta(7) integrin (beta(7) I) were then used to target specific leukocyte subsets involved in gut inflammation. Systemic application of beta(7) I-tsNPs silenced CyD1 in leukocytes and reversed experimentally induced colitis in mice by suppressing leukocyte proliferation and T helper cell 1 cytokine expression. This study reveals CyD1 to be a potential anti-inflammatory target, and suggests that the application of similar modes of targeting by siRNA may be feasible in other therapeutic settings.
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Kim D, Chun BG, Kim YK, Lee YH, Park CS, Jeon I, Cheong C, Hwang TS, Chung H, Gwag BJ, Hong KS, Song J. In vivo tracking of human mesenchymal stem cells in experimental stroke. Cell Transplant 2008; 16:1007-1012. [PMID: 18351016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
To understand the fates of human mesenchymal stem cells (hMSCs) following transplantation into a rodent model of middle cerebral artery occlusion (MCAo), magnetic resonance imaging (MRI) techniques were employed, hMSCs were labeled with ferumoxides (Feridex)--protamine sulfate complexes, which were visualized and examined by MRI up to 10 weeks following transplantation. Migration of the transplanted cells to the infarcted area was further confirmed by histological methods. We found that the hMSCs transplanted in MCAo models possess the capacity to migrate to the infarcted area extensively in both ipsilateral and contralateral injections, exhibiting a pathotropism. We also analyzed the detailed migration patterns of transplanted hMSCs. We speculate that the extensive migratory ability of hMSCs may represent a therapeutic potential for developing efficient cell transplantation strategies in stroke.
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JAQUES LB. A study of the toxicity of the protamine, salmine. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 2007; 4:135-44. [PMID: 18149707 DOI: 10.1111/j.1476-5381.1949.tb00526.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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70
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Arbab AS, Rad AM, Iskander ASM, Jafari-Khouzani K, Brown SL, Churchman JL, Ding G, Jiang Q, Frank JA, Soltanian-Zadeh H, Peck DJ. Magnetically-labeled sensitized splenocytes to identify glioma by MRI: a preliminary study. Magn Reson Med 2007; 58:519-26. [PMID: 17763342 DOI: 10.1002/mrm.21343] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
This study investigated the feasibility of imaging the migration and incorporation of magnetically-labeled sensitized splenocytes in an experimental 9L glioma brain tumor model. Splenocytes collected from tumor-bearing (sensitized splenocytes) or control (nonsensitized splenocytes) host rats were analyzed to determine the population of different cells, labeled with ferumoxides-protamine sulfate (FePro) and injected intravenously to recipient rats (N=4, for each group) bearing intracranial 9L tumors. Day 3 postinjection of splenocytes multiecho T2*-weighted and three-dimensional (3D) gradient echo MRI were obtained using a 7 Tesla MR system. R2* (1/T2*) maps were created from the T2*-weighted images. Signal intensities (SIs) and R2* values in the tumors and contralateral brain were determined by hand drawn regions of interest (ROIs). Brain sections were stained for the evidence of administered cells. Both 3D and T2*-weighted MRI showed low signal intensity areas in and around the tumors in rats that received labeled sensitized splenocytes. Prussian blue (PB), CD45- and CD8-positive cells were present in areas at the corresponding sites of low signal intensities seen on MRI. Rats that received labeled nonsensitized splenocytes did not show low signal intensity areas or PB positive cells in or around the implanted tumors. In conclusion, the immunogenic reaction can be exploited to delineate recurrent glioma using MRI following systemically delivered magnetically labeled sensitized splenocytes or T-cells.
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Cerná A, López-Fernández C, Fernández JL, Moreno Díaz de la Espina S, de la Torre C, Gosálvez J. Triplex configuration in the nick-free DNAs that constitute the chromosomal scaffolds in grasshopper spermatids. Chromosoma 2007; 117:15-24. [PMID: 17763864 DOI: 10.1007/s00412-007-0121-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Revised: 08/07/2007] [Accepted: 08/07/2007] [Indexed: 10/22/2022]
Abstract
After applying proper deoxyribonucleic acid (DNA) probes, fluorescence in situ hybridization (FISH) showed that the 8/9 centromeres-one per chromatid of the male haploid complement (X0) of Pyrgomorpha conica grasshopper-colocalized at the spermatid blunt end, where the spermatozoa flagellum inserts. A bundle of aligned 4',6-diamidino-2-phenylindole-positive chromatid scaffolds, which formed the central spermatid core, was observed after DNA breakage detection followed by FISH. Modular nature of scaffold DNA was occasionally evident. The technique also showed that in the early spermatid, the chromatid scaffolds lacked any DNA nick, whereas abundant breaks accumulated in the surrounding loops. Moreover, immunodetection showed that scaffold DNA participated in the formation of triplex DNA, while this configuration was absent from the loops. During spermatid maturation, triplex DNA disappeared from the scaffold in parallel with loop retraction, while protamines replace histones. Thus, the presence of triplex DNA in the chromatid scaffold correlates with the anchoring of expanded DNA loops to it. After loop retraction, the scaffolds of all chromatids coiled as a single unit in the spermatid head. This cooperative coiling produced enlargement and tilting of the distal telomeric signals, which were distributed along the spermatid head according to the length of each chromosome. We propose that specific DNA sequences dispersed throughout the whole chromatid fold forward and backward coaxially to chromatid length, forming individual scaffold modules whose linear assembly accounts for the minimum length of each individual chromatid. Finally, the core of the grasshopper male spermatid should be considered as a single chromosome in which the DNA scaffolds of the whole set of the nonhomologous chromosomes of the haploid complement are interconnected. This pattern of chromatin organization applies probably to other elongated spermatids.
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Suzuki Y, Zhang S, Kundu P, Yeung AC, Robbins RC, Yang PC. In vitro comparison of the biological effects of three transfection methods for magnetically labeling mouse embryonic stem cells with ferumoxides. Magn Reson Med 2007; 57:1173-9. [PMID: 17534917 DOI: 10.1002/mrm.21219] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In vivo MRI of stem cells (SCs) is an emerging application to evaluate the role of cell therapy in restoring the injured myocardium. The high spatial and temporal resolution combined with iron-oxide-based intracellular labeling techniques will provide a sensitive, noninvasive, dual imaging modality for both cells and myocardium. In order to facilitate this novel imaging approach, much effort has been directed towards developing efficient transfection methods. While techniques utilizing poly-L-lysine (PLL), protamine sulfate (PS), and electroporation (ELP) have been proposed, the fundamental biological effects of these methods on mouse embryonic SCs (mESC) have not been investigated systematically. In this study a longitudinal in vitro evaluation of cellular viability, apoptosis, proliferation, and cardiac differentiation of magnetically labeled mESC was conducted. No significant difference was seen in these biological parameters among the three transfection methods. However, cardiac differentiation was most attenuated by ELP, and iron uptake was most effective by PS.
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Sukavaneshvar S, Parker JT, Beutler DS, Burns G, Solen KA, Mohammad SF. Mitigation of coagulation by removing clotting factors part 2: heparin-free extracorporeal circulation in a porcine model. ASAIO J 2007; 53:421-7. [PMID: 17667225 DOI: 10.1097/mat.0b013e3180ca9a1e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
A subpopulation of patients would benefit from an anticoagulation strategy during extracorporeal circulation (ECC) that does not involve systemic administration of heparin and protamine. Inhibition of coagulation by adsorption of plasma clotting factors using protamine immobilized on a Sepharose matrix (PSM) has been explored. This investigation extends previous in vitro studies and demonstrates the feasibility of heparin-free ECC. In a porcine ex vivo circuit, plasma was separated from blood via plasmapheresis, passed through a column containing PSM beads, and returned to the animal. Hemodialyzers and stents were placed in the circuit before, during, and after ECC and examined for device thrombosis. After 90 minutes, prothrombin time (PT) was prolonged >10 times the baseline, and blood clotting Factors I, II, VIII, and X were decreased significantly (>90%); this state was maintained for 2.5 hours without detectable adverse consequences. After cessation of ECC, PT approached normal levels within 60 minutes. Examination of hemodialyzers and coronary stents placed in the circuit revealed that the removal of clotting factors significantly reduced device thrombosis and that transfusion of homologous blood ( approximately 10% V/V) resulted in immediate restoration of hemostasis. It is possible to remove clotting factors from circulating blood to allow extracorporeal circulation of blood without the use of heparin.
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Parker JT, Beutler DS, Sukavaneshvar S, Jacobs N, Solen KA, Mohammad SF. Mitigation of Coagulation by Removing Clotting Factors Part 1: In Vitro Feasibility Study. ASAIO J 2007; 53:415-20. [PMID: 17667224 DOI: 10.1097/mat.0b013e3180cab642] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Heparin is associated with adverse effects in some patients during extracorporeal circulation. A potential alternate anticoagulation strategy explored in this investigation involved mitigation of coagulation by removing clotting factors from blood by adsorption on a protamine-immobilized Sepharose matrix (PSM). Human or porcine plasmas treated with PSM in vitro were tested for clotting factors I (fibrinogen), II (prothrombin), VIII, and X, and proteins C and S, and for prothrombin time (PT), activated partial thromboplastin time (APTT), and total protein concentration. Bovine blood treated with PSM was also perfused through a hollow-fiber cartridge to assess thrombogenic potential in a shear flow system. PT increased with increasing protamine-Sepharose-to-plasma ratios and with increasing mixing time. When the PT and APTT of treated plasma were prolonged three to six times the baseline, Factors II and X were significantly removed (>90%), Factors I and VIII were partly removed (<35%), and total protein concentration remained >80% of the initial value. When blood depleted of clotting factors was perfused through hollow-fiber cartridges without an anticoagulant, cartridge patency was prolonged compared with cartridges perfused with untreated blood. This investigation demonstrated that inhibition of blood coagulation by removal of key clotting proteins is feasible.
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Freitas CF, Morganti RP, Annichino-Bizzacchi JM, De Nucci G, Antunes E. Effect of BAY 41-2272 in the pulmonary hypertension induced by heparin-protamine complex in anaesthetized dogs. Clin Exp Pharmacol Physiol 2007; 34:10-4. [PMID: 17201729 DOI: 10.1111/j.1440-1681.2007.04524.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1. BAY 41-2272 is a potent activator of the nitric oxide-independent site of soluble guanylate cyclase and has been recently introduced as a new therapeutic agent to treat chronic pulmonary hypertension (PH) in neonatal sheep. Because the in vivo heparin-protamine interaction may lead to severe PH, the aim of the present study was to evaluate the effects of BAY 41-2272 in the PH induced by heparin-protamine interaction in anaesthetized dogs. 2. Sixteen male dogs (10 mongrel dogs and six Beagles) were anaesthetized and instrumented for acquisition of mean arterial blood pressure (MABP), mean pulmonary arterial pressure (MPAP), heart rate (HR), pulmonary capillary wedge pressure (PCWP), cardiac index (CI) and indices of systemic and pulmonary vascular resistance (ISVR and IPVR, respectively). Plasma cGMP levels and S(p)o(2) were evaluated. 3. Intravenous administration of heparin (500 IU/kg) followed 3 min later by protamine (10 mg/kg) caused marked PH, as evaluated by the increase in MPAP, PCWP and IPVR. This was accompanied by a significant fall in MABP and a transient increase in HR. Infusion of BAY 41-2272 (10 microg/kg per h, starting 10 min before heparin administration) augmented plasma cGMP levels and slightly and significantly increased HR and CI, without affecting the other cardiovascular parameters. The elevation in IPVR, MPAP and PCWP triggered by the heparin-protamine interaction was significantly reduced in animals exposed to BAY 41-2272. 4. In vehicle-treated dogs, the S(p)o(2) values decreased significantly at the peak of the PH and this was significantly attenuated by treatment with BAY 41-2272. In addition, BAY 41-2272 (10 micromol/L) had no effect on the activated partial thromboplastin time of citrated plasma after the addition of heparin-protamine. 5. In conclusion, BAY 41-2272 was effective in reducing canine PH induced in vivo by the heparin-protamine interaction, thus indicating its potential in the treatment of this type of disorder.
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