Blood is a complex mixture of formed cellular elements, proteins, and ions dissolved in a solution. It is a difficult fluid to model because it is a shear-thinning, viscoelastic fluid that stress- relaxes. In this study, a new mathematical model for whole blood is developed from a general equation for a fluid with a shear dependent viscosity. The model is then used as a backdrop for 28 different biochemical factors interacting to form a clot. The full intrinsic and extrinsic pathways are both used in the simulation; the inclusion of the full intrinsic pathway is something that had not been done prior to this work. The model is executed in one spatial direction in an infinite domain as well as within a rigid walled cylinder using a finite volume scheme. The rigid wall, similar to the new mathematical equation for blood, is an oversimplification of actual in-vitro conditions. The results of both simulations show the formation and dissolution of the clot. Sensitivity analysis is then performed in the finite domain model by adjusting the initial levels of factors Va and Xa. The results show that by increasing the initial level of one or both of these factors leads to the quicker formation of a clot.

An individual who is diagnosed with an inherited bleeding disorder is expected to manage his or her condition on a daily basis. This chronic situation can totally disrupt psychosocial functioning and make it more difficult to adjust to the illness. Other researchers have studied this phenomenon in various other chronic illnesses; however, not in individuals with inherited bleeding disorders (Akkasilpa, et al, 2000, Pollack, 1989a, 1989b). Psychosocial problems are not restricted to individuals with one chronic illness and clinically, it is noted that some individuals adjust to chronic diseases better than others. Individuals living with inherited bleeding disorders may also have other chronic illnesses such as hypertension, asthma, diabetes mellitus (DM), congestive heart failure (CHF), arthritis, and hepatitis A, B, C and/or HN. The aims of this study are to describe health stressors, health related hardiness, perception of illness impact, self perception of health status and psychosocial adjustment to illness in individuals living with an inherited bleeding disorder; to determine relationships between demographic and illness variables, health stressors, health related hardiness, perception of illness impact, self­ perception of health status and psychosocial adjustment to illness; and to determine if perception of illness impact has a direct and/or mediating effect on the relationship between health stressors, health related hardiness, and self-perception ofhealth status and psychosocial adjustment to illness. A cross sectional survey design was used in this study. Sixty individuals of predominantly Asian Pacific Islander ethnicity diagnosed with hemophilia, von Willebrand's Disease, Factor V or as hemophilia carriers comprised the sample which was drawn from the Hemophilia Treatment Center of Hawaii. All participants were asked to complete five questionnaires: Demographic form and illness information, health related hardiness scale (Pollock, 1990), perception of illness impact scale, self-perception of health status and psychosocial adjustment to illness scale (Derogatis, 1990). Higher health stressors were associated with higher perception of illness impact, lower perception of health status and poorer psychosocial adjustment to illness. Individuals with higher hardiness were better adjusted to their illness. Higher perception of illness impact was associated with lower self-perception of health status and poorer psychosocial adjustment to illness. Higher self-perception of health status was associated with better psychosocial adjustment to illness. Perception of illness impact did mediate the relationship between health related hardiness and psychosocial adjustment to illness. Perception of illness impact did not mediate the relationship between health stressors and psychosocial adjustment to illness, between health stressors and self-perception of health status, and between health related hardiness and self-perception of health status. The knowledge generated from this study has the potential to impact the existing practices in improving evidence-based nursing practice in caring for individuals with inherited bleeding disorders. Future research is indicated with a large sample to determine differences between diagnosed individuals and carriers, between various Asian Pacific Islander cultural groups, and to determine replicability of the findings from this smaller study sample.

Thesis (M.Med.Sc.) -- University of Adelaide, Dept. of Clinical and Experimental Pharmacology, 2000. / Bibliography: leaves 115-125.

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Thesis (MTech(Medical Technology))--Cape Technikon, 1997 / Cryoprecipitates are used as the raw material for the preparation of Factor VIII (FVIIIl) for replacement therapy for haemophiliacs. Routinely, cryoprecipitate only recovers 50% of the Factor VIII in the plasma. The purpose of this study, production of cryoprecipitate, was to investigate those variables which play a key role in determining the yield of Factor VIII present in cryoprecipitate. Cryoprecipitate production involves a wide range of variables which could effect the final outcome of the product. These vary from the donor blood group, time of donation, exercise levels of the donor, to a time delay prior to processing, temperature storage conditions, to the method utilised for plasma freezing and thawing. The objective was to explore which combination of variables in the procedure would lead to a process which would optimize the preparation of cryoprecipitate in a routine environment, to yield the highest levels of Factor VIII. Frequently in scientific investigations, particularly when a practical approach has to be adopted, questions arise in which the effects of a number of different variables in a process, require evaluation. Such questions can usually be most economically investigated, by arranging the analysis according to an ordered plan in which all the factors are viewed in a regular way. Provided the plan has been correctly chosen, it is possible to determine not only the effect of each individual variable, but also the way in which each effect depends on the other factor, by means of an interaction. This makes it possible to obtain a more complete picture of what is happening, than would have been obtained by varying each of the variables one at a time while keeping the others constant. Designs of this sort lend themselves well to statistical analysis, and provide their own estimates of experimental error. This type of statistical analysis called, 2K Fractional Factorial Experimental Design, forms the basis of this study in which 14 key variables in the production process of cryoprecipitate were defined as possible areas in which Factor VIII levels in the cryoprecipitate are effected. Key variables have been identified on an individual basis in previous studies (Burka et al., 1975), however this blended approach to optimise the key variables within the production environment, and define further combinations which could be incorporated into the production, has never been attempted. The statistical design used in the study was compiled by the Institute for Biostatistics of the Medical Research Council (MRC). Units of blood were collected and processed, from blood donors under the stipulated criteria, corresponding to the study design.

Made available in DSpace on 2014-10-09T12:52:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:51Z (GMT). No. of bitstreams: 0 / O veneno de C. d. terrificus tem sido descrito como sendo de pouca complexidade, tendo 4 frações caracterizadas, convulxina, giroxina. crotoxina e crotamina. O presente trabalho visou o isolamento e caracterização da Delta toxina cuja existência havia sido aventada em trabalhos anteriores. Após a realização de uma varredura de tampões em uma coluna de exclusão molecular Superdex-75 acoplada a um sistema FPLC, na presença de três diferentes tampões, chegou-se a uma condição ideal de fracionamento do veneno crotálico. Em seqüência realizou-se a segunda etapa de purificação em sistema HPLC em uma coluna C4, onde foi possível identificar o pico de interesse. O pico puro passou por análises em MALDI-ToF sendo sua massa estimada em 14.074,92 Da, Quando analisado por eletroforese em gel de poiiacrilamida, a delta toxina apresentou massa molecular de cerca de 14 kDa e uma migração anômala, Por eletroforese 2D, a proteína apresentou caráter ácido, com pl entre 4 e 5 e massa molecular de aproximadamente 42 kDa, revelando \"spots\" muito semelhantes podendo ser isoformas com características de uma proteína glicosiiada. Após digestão dos spots com tripsina, os fragmentos foram confrontados com o banco de dados do \"swissprot\", mostrando alto grau de homologia \"até 43% de cobertura\" com a troca ri na, um ativador de protrombina do veneno de Tropidechis carinatus, esses dados foram confirmados com a análise de aminoácidos. De posse desses resultados, optou-se por testar a capacidade da fração purificada de ativar fator X e II, usando substratos sintéticos. Os resultados apontaram para uma ativação direta do fator X, uma vez que não houve ativação do fator II, atividade que também não foi detectada no veneno total. A mesma se mostrou um potente ativador da agregação de forma direta, uma vez que os ensaios de agregação plaquetária foram realizados com plaquetas lavadas, logo na ausência de fatores séricos. Quando os ensaios de agregação foram realizados na presença de alguns inibidores observou-se que nem a atividade metalo proteinase, nem a serino proteinase, tampouco um domínio lectina estavam envolvidos no processo, uma vez que EDTA, benzamidina e D-galactose não inibiram a atividade da proteína. No presente trabalho isolamos a Delta toxina do veneno de C. d. terrificus. A mesma se comportou como previsto por Vital Brazil em 1980, eluindo na posição por ele aventada, sendo uma proteína ativadora de Fator X que ativa agregação plaquetária mesmo em concentrações muito baixas e de massa molecular de 40 kDa levando nos a crer se tratar de um homotrímero cujos componentes são unidos por ligações fracas. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

No description available.

M.Tech. / The homoeopathic medicine Arnica montana is often prescribed in cases of trauma, before and after surgery and in cases where there is bleeding. Many conventional medical practitioners, however, do not advise its use for the above complaints due to the herbally prepared Arnica montana mother tincture containing coumarin derivatives which are said to have an anti-coagulant effect and cause a potential risk of bleeding. The aim of this particular study was to investigate the in vivo effect of the complex remedy Arnica montana composing of potencies 6C, 30C and 200C on coagulation and bleeding. This study forms part of a three part in vivo study to determine the effect of homoeopathic Arnica montana in various potencies on blood coagulation. The effect of Arnica montana on blood coagulation was evaluated by measuring the Bleeding Time (BT), activated Partial Thromboplastin Time (aPTT) and Prothrombin Time (PT). This is a double blind, placebo controlled trial with a total sample group of eighty healthy participants between the ages of eighteen to thirty five. As this study forms part of a three part study the total sample group was shared. Twenty participants were allocated to the placebo group and received 20% ethanol. Twenty participants were allocated to the experimental group and received the complex homoeopathic preparation of Arnica montana 6C, 30C and 200C in 20% ethanol. The Bleeding Time was measured by a trained medical technologist and blood samples underwent coagulation tests comprising of aPTT and PT. The study was conducted over a period of two weeks at the UJ Doornfontein Campus Homoeopathy Health Centre. After two weeks another venous sample was drawn by the phlebotomist and sent away for the same coagulation studies as described above. The technologist again measured the Bleeding Time. Results obtained from the Prothrombin Time, activated Partial Thromboplastin Time and Bleeding Time tests pre- and post medication were compared and v analysed. Analysis of data was done using SPSS 15.0 (Statistical Package for Social Sciences). Results showed that complex remedy Arnica montana 6C, 30C and 200C had no significant effect on blood coagulation and bleeding in vivo.

By specifically analysing for the various active principles of plasma, platelets, tissues and their fractions, much new information has been obtained concerning the role of lipoids and platelets in blood coagulation and in the hemostatic mechanisms in health and disease. Analysed components are studied in artificial clotting systems, especially a two-stage thrombin- forming system. Some 86 cases of bleeding disorders, 32 new born normal infants and their mothers, and many normal adult bloods have been analysed with respect to components of the clotting and hemostatic functions. The detailed considerations embodied in the thesis are encompassed under the following heads: 1) the importance of certain lipoids, especially cephalin 2) the normal need, in plasma clotting, for platelets, 3) the particular significance of a platelet component, which has many analogies to cephalin, in the thromboplastic system, 4) potentiation of the thromboplastic actions of cephalin, of platelets, and of tissue thromboplastin (to some extent) by a variety of experimental additives. Part of this may be explained as a 'thromboplastin generation' through co-participation of certain plasmatic components (antihemophilic globulin, PTC" etc. ) . Part, however, may be the result of certain proteolytic enzymes, particularly trypsin, 'disaggregating' lipoproteins and thus rendering their phospholipid (and sometimes calcium) available for participation in the clotting reactions, 5) possible Ca-containing and lipid-containing 'intermediates’ in the thrombin-forming reactions, 6) myelin figure formation as an explanation of ‘alterations' of platelets and certain other formed elements such as thrombocytes, megakaryocytes, and stromatolytic erythrocytes 7) the multiplicity of factors which platelets may contribute to the blood clotting and hemostatic mechanisms 8) the occurrence of many clinical disorders due to deficiency of platelet functions. Thrombocytopenias denote deficient numbers ('counts' and total bulk in body). Thrombocytopathies are deficiencies of specific platelet components, e . g. thromboplastic factor, accelerator, vasoconstrictor (5-hydroxy tryptamine), or retractor factor. Such deficiencies can be clinically significant even when the platelet count is normal. Bleeding in leukaemias, uremias, etc. may often be accounted for in these terms, 9) the nature and modes of action of heparin and other 'antithromboplastic’ inhibitors, and of some antiproteases, in relation to the mechanisms discussed 10) the ‘cephalin availability theory' of the author, as a useful working hypothesis to explain the importance of the natural thromboplastic phospholipid. Lipid release from platelet, tissue, or possibly plasma sources may very well be the long-obscure 'trigger mechanism' which initiates blood coagulation.

No description available.