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Pre-coagulation of solid organsDaniel, Steven A., School of Medicine, UNSW January 2007 (has links)
Coagulation has and continues to be one of the most important elements in medicine. Issues from a lack of hemostasis range from poorer clinical outcomes to sudden death. The evolution of treatments for hemostasis have evolved from the use of Tamponade with direct pressure and bandages, the use of materials such as cobwebs and dust, the use of heat with hot oil or heated irons, to the use of suture, glues, plasmas, staplers, and electricity. This evolution has continued to bring about the prophylactic use of technology in an effort to prevent blood loss. This change from reactive treatments to proactive continue to be on a localized or superficial basis. One of the largest opportunities to proactively reduce blood loss in surgical patients is during the resection of solid organs such as the liver, kidney, and spleen. Few options have existed to help improve hemostasis short of the complete occlusion of blood supplying the tissue such as in the Pringle Maneuver. Recent studies have begun to show that practices such as this may have a significant detrimental effect on morbidity. It has been found that by applying radio frequency electrical energy in a particular way that large amounts of tissue can be pre-coagulated prior to resection. A series of animal and human clinical work has been completed to help evolve and confirm the method and the device that was created and refined during this effort. During the course of this work fifty-three patients were treated at four institutions on three continents. Average blood loss for liver resections performed with this pre-coagulation technique using the developed device in a multicenter control trail was 3.35 ml/cm2 as compared to 6.09 ml/cm2 (p < 0.05) for resections performed using standard surgical techniques alone. Additionally, the transection time necessary was also reduced from mean value of 27 minutes (2 -- 219 minutes) to 35 minutes (5 -- 65 minutes). Patients treated included those suffering from liver cirrhosis, fatty liver disease, and post chemotherapy fibrosis. From this work the use of pre-coagulation with methods and device developed was shown to be safe and effective for reducing the amount of blood loss and transection time during liver resections.
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GAG inhibition of collagen-platelet interactionSilver, Frederick Howard. January 1977 (has links)
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 1977 / Includes bibliographical references. / by Frederick H. Silver. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Efeito de diferentes intensidades de exercício aeróbio prévio, sobre a curva lipêmica, inflamação e hemostasia de sujeitos submetidos à refeição hiperlipídicaTeixeira, Bruno Costa January 2016 (has links)
Introdução: O consumo habitual de refeições ricas em gordura tem se mostrado indutor de doenças cardiovasculares (DCV), afetando o equilíbrio entre os sistemas de coagulação e fibrinólise e também induzindo o aumento de marcadores inflamatórios. Por outro lado, o exercício físico tem sido indicado como intervenção por atenuar o incremento da inflamação e equilibrar os sistemas hemostáticos em indivíduos que consomem uma refeição hiperlipídica (RH). Objetivo: Verificar o efeito subagudo de duas sessões com intensidades diferentes de exercício aeróbio na curva lipêmica, inflamação, hemostasia em sujeitos jovens saudáveis submetidos à refeição hiperlipídica. Metodologia: Onze sujeitos eutróficos do sexo masculino, fisicamente ativos, com idade média de 23 ± 3 anos participaram do estudo que foi composto por três protocolos com dois dias consecutivos cada. No dia 1 os sujeitos realizavam um dos três protocolos que era realizado de forma randomizada, os protocolos eram divididos em: exercício de baixa intensidade (BI), exercício de moderada intensidade (MI) e repouso (Con). No dia dois 12h após a realização do exercício prévio os sujeitos consumiam uma RH (15% proteínas, 35% carboidratos e 50% lipídeos). Foram realizadas coletas de sangue para analise de triglicerídeos (TG), Colesterol total (CT), lipoproteínas de alta densidade (HDL), lipoproteínas de baixa densidade (HDL) e Glicose, no basal (BS) e a cada hora de 1 à 5h após a RH. As coletas sanguíneas para análise de Ativador de plasminogênio (tPA), Inibidor do ativador de plasminogênio do tipo 1 (PAI-1), Fator de necrose tumoral alfa (TNFα), Interleucina 6 (IL-6) e Interleucina 10 (IL-10) foram realizadas no momento basal, 1h, 3h e 5h após a RH. Resultados: Os protocolos BI e MI apresentaram menor área abaixo da curva (AUC) de TG em relação ao Con (P<0,05). Houve diferença significativa no PAI-1 em relação ao BI quando comparado ao MI e Con e de tPA do protocolo BI em relação ao Con no momento 1h pós refeição (P<0,05). No FVII, os protocolos MI e BI foram significativamente menores que o Con no momento 1h pós RH (p<0,05). Houve diferença significativa em TNFα entre os protocolos MI e Con no momento 1h pós RH (P<0,05) e foram encontradas diferenças em IL-10 nos protocolos MI e Con nos momentos 1h e entre os protocolos MI e BI nos momentos 1h, 3h e 5h pós RH (P<0,05). Houve diferença em IL-6 em todos os momentos de todos os protocolos em relação ao momento basal (BS). Conclusão: A RH aumenta o estado inflamatório e desregula o equilíbrio entre coagulação e fibrinólise, o protocolo BI e MI atenuam a curva de TG em relação ao Con, o protocolo MI melhorou o estado inflamatório diminuindo TNFα e incrementado IL-10 e o protocolo BI melhorou a relação entre coagulação e fibrinólise atenuando a diminuição de tPA e diminuindo o incremento de PAI-1 e ambos os protocolos MI e BI não incrementaram FVII 1h após RH. / Background: Regular consumption of high-fat meals has been considered to play a role in the development of cardiovascular diseases. The increase of postprandial lipemia after a high-fat meal consumption can imbalance the relationship between coagulation and fibrinolysis and, by consequence, enhance an inflammatory response. Conversely, exercise has been considered an important intervention, once it may attenuate inflammatory responses and counterbalance hemostatic systems during the postprandial period. Purpose: Verify the subacute effect of two exercise bouts performed at different intensities on postprandial lipemia, inflammation and hemostasis after the consumption of a high-fat meal. Methods: Eleven healthy and physically active male subjects with average age of 23 ± 3 years completed 2-day trials in three conditions: Control, low-intensity exercise (LI) and moderate-intensity exercise (MI). Subjects performed an exercise bout (LI or MI) or no exercise (Control) on the evening of day 1. On the morning of day 2, a high-fat meal was provided (15 % of protein, 35 % of carbohydrates and 50 % of lipids). Blood was sampled at fasting (0 h) and every hour from 1 to 5 h for triglycerides (TG), total cholesterol, HDL, LDL and glucose. For plasminogen activator inhibitor-1 (PAI-1), plasminogen activator (tPA), tumor necrosis factor-alpha (TNFα), interleukin-6 (IL-6) and interleukin-10 (IL- 10), blood was sampled at 0, 1, 3 and 5 h. Results: TG area under the curve (AUC) was lower in LI and MI than Control (P<0.05). For PAI-1, there was a difference from LI to MI and Control at 1 h (P<0.05). For tPA, there was a difference from LI to Control at 1 h (P<0.05). For FVII the protocols MI and BI there was difference from Con in at 1h. For TNFα, there was a difference from MI to Control at 1 h (P<0.05). IL-10 concentration was different from MI to Control at 1 h and from MI to LI at 1, 3 and 5 h (P<0.05). Fasting IL-6 concentrations were different between all conditions (P<0.05). Conclusion: The consumption of a high-fat meal increases the inflammatory process and deregulates the balance between coagulation and fibrinolysis. Exercise, independent of the intensity, can reduce TG AUC compared to Control. MI can reduce TNFα and increases IL-10, while LI regulates coagulation and fibrinolysis balance, which can be explained by the increase in tPA and increase in PAI-1.
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Tromboelastometria (ROTEM) em gatos da raça Maine Coon portadores e não portadores da mutação (A31P) no gene MYBPC3 para miocardiopatia hipertróficaAssunção, Pedrita Carvalho Ferreira. January 2019 (has links)
Orientador: Regina Kiomi Takahira / Resumo: A miocardiopatia hipertrófica é a doença cardíaca mais observada em gatos da raça Maine Coon e está diretamente relacionada à presença de uma mutação (A31P) que ocorre no gene da proteína C miosina ligante (MYBPC3). A doença pode provocar em determinados pacientes quadros secundários graves como o tromboembolismo arterial (TEA). O objetivo do presente trabalho foi avaliar gatos da raça Maine Coon não portadores da mutação A31P no gene MYBPC3 (G1) e portadores da mutação A31P no gene MYBPC3 (G2), por meio do perfil tromboelastométrico. Foram selecionados no estudo 15 gatos pertencentes ao grupo G1 e 15 gatos G2, previamente avaliados para A31P-MYBPC3, tendo como critério de inclusão a presença ou não da mutação e higidez clínica e laboratorial para hemograma e provas de bioquímicas séricas. A coleta das amostras ocorreu em momento único após avaliação ecocardiográfica. A análise estatística foi realizada por meio de análise descritiva dos dados seguida da comparação dos grupos ao nível de 5 % de significância. No presente estudo o perfil pela tromboelastometria (TEM) não identificou diferenças quando comparados os grupos G1 e G2, portanto os animais não demonstraram variações de coagulabilidade. A concentração sérica de albumina foi significativamente menor no G2, mas se manteve dentro dos intervalos de referência para a espécie. No ecocardiograma foi observada alteração no volume diastólico final no G2, indicando a presença de possível disfunção diastólica. O G2 também aprese... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Hypertrophic cardiomyopathy is the most observed heart disease in Maine Coon cats and is directly related to the presence of a mutation (A31P) occurring in the myosin binding protein C (MYBPC3) gene. The disease can cause serious side effects such as arterial thromboembolism (ATE) in certain patients. The objective of the present study was to evaluate the thromboelastometric profile in cats Maine Coon breed without mutation A31P on MYBPC3 gene (G1) and mutation carrier (G2). Thirty cats previously evaluated for A31P-MYBPC3 were divided into G1 and G2 groups (n=15). The inclusion criteria were the presence or absence of mutation and clinical data, blood counts and serum biochemistry within reference intervals. The samples were taken at a single moment after an echocardiographic evaluation. Statistical analysis was performed through descriptive data analysis followed by comparison of groups at the 5% level of significance. In the present study, the profile by thromboelastometry (TEM) did not identify differences when comparing groups G1 and G2, and the animals showed no coagulability variations. Serum albumin concentration was significantly lower in the mutation carrier group (G2), but it remained within the reference intervals for the species. On the echocardiogram, a change in final diastolic volume was observed in the carrier group, indicating that the carrier animals should be evaluated to previous identification of possible diastolic dysfunction. The carrier group also pre... (Complete abstract click electronic access below) / Doutor
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Interventional cardiology: a portfolio of research pertaining to femoral sheath removal practices and patient educationJones, Tina. January 2003 (has links) (PDF)
"March 2003" Includes bibliographical references (leaves 61-68). Appendices: Publications arising from the research portfolio. 1. Conducting a systematic review -- 2. The effectiveness of mechanical compression devices in attaining hemostasis after removal of a femoral sheath following femoral artery cannulation for cardiac interventional procedures : a systematic review -- 3. Effectiveness of mechanical compression devices in attaining hemostasis after femoral sheath removal Contains three separate research projects, presented as separate reports, but all related to one area of interest - interventional cardiology. Seeks to identify effective femoral sheath removal practices after interventional cardiac procedures and determine patient's perceptions of the education prior to and after interventional procedures.
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Hormonal regulation of the anticoagulant Protein SHughes, Qunitin William January 2008 (has links)
[Truncated abstract] Every year thousands of individuals suffer from thrombotic related complications that in some cases can be fatal and every year millions of women take some form of hormonal contraceptive. In some cases, there is a cause and effect relationship between the two as users of the combined oral contraceptive pill have an increased risk of developing a thrombotic event. Increased circulating levels of oestrogen cause a prothrombotic shift in the coagulation cascade resulting from upregulation of several procoagulant proteins and a decrease of key anticoagulant proteins. One of the most oestrogen sensitive anticoagulants is Protein S (PS), a product of the PROS1 gene. PS acts as a cofactor to activated protein C (aPC) and the PS-aPC complex serves to downregulate clot formation by deactivating the tenase and prothrombinase complexes via proteolytic cleavage of activated factors VIII and V, respectively. As such, low PS levels are associated with an increased risk of developing thrombotic disorders such as pulmonary embolism, stroke or coronary thrombosis and deep vein thrombosis. During pregnancy when oestrogen levels increase, a steady decline in PS is evident in the early weeks of gestation and continues to decrease to below the normal range in the 2nd trimester, remaining there until post-partum. In addition, reduced free and total PS levels are observed in users of the combined oral contraceptive (COC) pill that contains an oestrogen and a progestin. Interestingly, users of 3rd generation COCs have significantly greater reductions of PS than do 2nd generation COC users. The difference between the two forms is the type of progestin, not the oestrogen, which is predominantly ethinyl oestradiol in the majority of commercially available preparations. At present, a mechanism to describe the relationship between oestrogen and/or progesterone associated with the observed in vivo changes in the levels of PS has not been identified. The aim of this thesis was to define the molecular mechanisms involved in the regulation of PS expression by oestrogen and progesterone. In this study, a Combined Single-stranded conformational analysis and Heteroduplex Analysis (CSHA) iv methodology was optimised for screening both PROS1 DNA and mRNA for the detection of mutations. '...' This may explain why users of 3rd generation COCs display a greater reduction in circulating PS levels compared to 2nd generation users. To investigate potential PS interactions with other proteins that could be hormonally regulated, a yeast-2-hybrid (Y-2-H) screen was performed using the PS molecule as a 'bait' against molecules derived from liver and bone marrow cDNA libraries. A clone that contained a portion of another haemostatic protein, Protein Z (PZ) was isolated and confirmed via sequencing. As no full length PZ clones were identified, a second Y-2-H screen was performed once again using the PS molecule as bait and the PZ molecule as the fish. Interaction between the two proteins was shown to be possible via the successful growth of colonies on triple knock out selective media and by positive ß-galactosidase activity.
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Interventional cardiology: a portfolio of research pertaining to femoral sheath removal practices and patient education / Tina Jones.Jones, Tina January 2003 (has links)
"March 2003" / Includes bibliographical references (leaves 61-68). / 1 v. (various pagings) : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Contains three separate research projects, presented as separate reports, but all related to one area of interest - interventional cardiology. Seeks to identify effective femoral sheath removal practices after interventional cardiac procedures and determine patient's perceptions of the education prior to and after interventional procedures. / Thesis (D.Nurs.Sc.)--University of Adelaide, Dept. of Clinical Nursing, 2003
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Μέθοδος ταχείας μέτρησης του χρόνου πήξης αίματος με τη χρήση μαγνητοσυστολικού αισθητήραΘεοδωράκης, Λάμπρος 13 June 2008 (has links)
Στο παρών κείμενο μεταπτυχιακής εργασίας περιγράφεται η κλινική εφαρμογή μαγνητοσυστολικού αισθητήρα για τη μέτρηση του χρόνου πήξης ολικού αίματος. Περιγράφεται η αρχή λειτουργίας της συσκευής και η κατασκευή του πρωτότυπου μοντέλου. Τα επιμέρους κομμάτια της διάταξης σχεδιάστηκαν, μελετήθηκαν και υλοποιήθηκαν ειδικά για τη συγκεκριμένη εφαρμογή. Με τη χρήση της συσκευής, το βιολογικό φαινόμενο της πήξης του αίματος μετατρέπεται σε εύκολα μετρούμενο σήμα ηλεκτρικής τάσης. Η μετατροπή αυτή γίνεται με τη βοήθεια διάταξης επαγωγικών πηνίων (διέγερσης-λήψης), στο εσωτερικό των οποίων τοποθετείται μαγνητοελαστικό υλικό. Στην επιφάνεια του υλικού τοποθετείται σταγόνα (2 μl) τριχοειδικού αίματος. Η μεταβολή των ιξωδοελαστικών χαρακτηριστικών του δείγματος καθώς αυτό περνάει από την υγρή στη στέρεα φάση (θρόμβος), ανιχνεύονται μέσω της αντίστοιχης μεταβολής της διαπερατότητας του υλικού. Το αποτέλεσμα της μέτρησης είναι γράφημα τάσης-χρόνου. Από το γράφημα του κάθε δείγματος που μετρήθηκε με τη συσκευή κατά τη διάρκεια της κλινικής εφαρμογής του στο Ιπποκράτειο Νοσοκομείο Αθηνών, προέκυψε ένας πειραματικός χρόνος, ο χρόνος πήξης tπηξ. Ο χρόνος αυτός αποδείχθηκε ότι έχει στατιστικά σημαντική σχέση με τον εργαστηριακό χρόνο ροής ΒΤ (Bleeding Time) (p<0.01). Η πήξη του αίματος αποτελεί το σημαντικότερο κομμάτι του αιμοστατικού μηχανισμού του ανθρώπινου οργανισμού. Διαταραχές που σχετίζονται με δυσλειτουργίες του μηχανισμού αυτού θεωρούνται ιδιαίτερα κρίσιμες και απαιτούν άμεση διάγνωση και βέλτιστη θεραπευτική προσέγγιση. Υπό το πρίσμα αυτών των απαιτήσεων, η υλοποίηση της συγκεκριμένης αισθητήριας εφαρμογής προσβλέπει στη διερεύνηση μιας νέας απλής και οικονομικής μεθόδου για την εξέταση δειγμάτων αίματος, όσον αφορά την πήξη τους. / The present master thesis describes the principle of operation, the construction, and the clinical evaluation of a whole blood coagulation magnetostrictive sensor. The major parts of the setup where specially designed and constructed for the needs of the present implementation. The function of the sensor relates to the transformation of the biological process of blood, into an easy-to-measure voltage signal. This transformation is feasible with the placement of a magnetoelastic material inside a double coil setup (primary-secondary). A drop of capillary blood (2 μl) is placed on the surface of the material. Viscosity variations of the sample, while it passes from the liquid to the solid phase, are detected through the detection of the corresponding permeability variations of the material. The result of the measurements which took place at the Hippokratio Hospital of Athens, is a V(t) graph. For each sample which was measured, the corresponding graph was used to export the experimental value tcoag. This value was proved to have a statistically significant relationship with Bleeding Time (BT) (p<0.01). Blood coagulation is the most important part of the human hemostatic mechanism. The disorders relating to the dysfunction of this mechanism are considered critical and demand immediate diagnosis and optimum therapeutic approach. Under this view, the realization of the specific sensor apparatus targets to the investigation of a new simple and cost-effective method for blood coagulation testing.
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Interventional cardiology: a portfolio of research pertaining to femoral sheath removal practices and patient education /Jones, Tina. January 2003 (has links) (PDF)
Thesis (D.Nurs.Sc.)--University of Adelaide, Dept. of Clinical Nursing, 2003. / "March 2003" Includes bibliographical references (leaves 61-68).
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Development of the clot formation and lysis (CloFAL) global assay and its application to the investigation of bleeding disorders in children and adults /Goldenberg, Neil A. January 2008 (has links)
Thesis (Ph.D. in Clinical Science) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 136-146). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;
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