Une des propriétés majeures de la thrombine est le caractère pléiotropique de ses effets physiologiques et pathologiques, à la fois dans le compartiment sanguin et tissulaire de la paroi. Notre hypothèse est que les changements phénotypiques des cellules musculaires lisses vasculaires (CMLVs) participent aux modifications des propriétés pro- et anticoagulantes de la paroi. Les objectifs ont été d’étudier : (i) le rôle prothrombotique des CMLVs dans l’hypertension chez le rat SHR et le syndrome métabolique (Smet) chez le rat Zucker, (ii) les mécanismes de régulation de la génération de thrombine par l’intégrine αvβ3 des CMLVs (récepteur de la pro- thrombine), et de développer des glyco-peptides fluorés pour l’imagerie permettant d’évaluer l’activité de cette intégrine dans la paroi, et (iii) d’évaluer l’effet de variants génétiques du locus 9p21 de susceptibilité aux maladies coronariennes sur le phénotype de coagulation. Résultats : Les CMLVs sont responsables du phénotype prothrombotique de la paroi artérielle associée à l’hypertension chez le rat SHR. Les acides gras libres et l’inflammation vasculaire augmentent la génération de thrombine dans les 2 compartiments ce qui se traduit par une fibrinolyse diminuée et une activité métallo-protéinase augmentée chez Le rat Zucker. L’invalidation de l’intégrine αvβ3 des CMLVs diminue la génération de thrombine dans les 2 compartiments et ralentit la survenue de thrombose carotidienne en réponse à une stimulation l’angiotensine. Le traçage de l’intégrine αvβ3 par des glyco-peptides comprenant une séquence RGD a été validé au niveau plaquettaire et des CMLVs. La souris invalidée pour le locus 9p21 exprime un phénotype pro-thrombotique qui est retrouvé chez l’homme pour certains variants (rs10120688 et rs1333040) dans ce locus. En conclusion, la CML est un support cellulaire clé de réactions procoagulants et pourrait être impliqué via les intégrines et/ou ses récepteurs pour la thrombine dans un couplage thrombine tissulaire – rigidité cellulaire dans les pathologies vasculaires / One of the major properties of thrombin is the pleiotropic character of its physiological and pathological effects, both in the blood compartment and the tissue of the arterial wall. We hypothesized that the phenotypic changes of vascular smooth muscle cells (VSMCs) are involved in modifications of pro- and anti-coagulant properties of the arterial wall. The objectives were to examine: (i) the prothrombotic role of VSMCs in hypertension of SHR rats and in the metabolic syndrome (Smet) of Zucker rats, (ii) regulatory mechanisms of thrombin generation by integrin αvβ3 of VSMCs (a pro-thrombin receptor), and to develop fluorinated glyco- peptides for imaging, to assess the activity of this integrin in the wall, and (iii) evaluate the effect of genetic variants of the 9p21 locus that give a susceptibility to coronary heart disease on the coagulation phenotype. Results: The VSMCs are responsible for the prothrombotic phenotype of the arterial wall associated with hypertension in SHR rats. Free fatty acids and vascular inflammation increase thrombin generation in the two compartments resulting in decreased fibrinolysis and an increased metallo-proteinase activity in the Zucker rats. The invalidation of integrin αvβ3 of VSMCs reduced thrombin generation in the two compartments and slowed angiotensin-induced carotid thrombosis. Tracing of the integrin αvβ3 by glyco-peptides including RGD was validated at the platelet level and VSMCs. Mice invalidated for the 9p21 locus express a prothrombotic phenotype that is found in humans for certain variants (rs10120688 and rs1333040) in this locus. In conclusion, the VSMC is a cell supported key to procoagulant reactions and may be involved via integrins and/or its receptors for thrombin in the ”tissular thrombin - cell rigidity” coupling in vascular pathologies

A Coagulação Intravascular Disseminada (CID) é uma síndrome caracterizada pela ativação sistêmica da coagulação sanguínea, levando à trombose microvascular difusa e podendo comprometer a função de múltiplos órgãos. O acelerado consumo de plaquetas e fatores de coagulação pode, no entanto, dar origem a um estado de hipocoagulabilidade, o que confere à CID uma característica paradoxal na qual o excesso de coagulação pode causar uma diátese hemorrágica. Doenças que levam à Síndrome de Resposta Inflamatória Sistêmica (SIRS) estão entre os principais gatilhos da CID. A pancreatite é uma dessas doenças. O maior desafio para o médico veterinário é diagnosticar a CID na fase precoce, silenciosa e de hipercoagulabilidade, visto que os testes laboratoriais de rotina, como contagem de plaquetas, tempo de protrombina (TP) e tempo de tromboplastina parcial ativada (TTPA), detectam apenas o estado de hipocoaguabilidade, que se estabelece na fase mais avançada da síndrome. Nesse contexto ganham importância os analisadores tromboelastográficos, equipamentos que avaliam a coagulação em sangue total e que, ao menos em tese, podem informar a velocidade de formação do coágulo, a força máxima que ele atinge e os padrões de sua dissolução. Este estudo é o primeiro realizado em cães com o aparelho ReoRox G2 (MediRox), uma da marcas disponíveis no mercado. Limites de referência para as variáveis do aparelho foram definidos a partir da análise do sangue de 49 animais clinicamente saudáveis para três tipos de reação: acelerada com fator tecidual (TF), acelerada com TF e um antagonista de agregação plaquetária (abciximab) e apenas com sangue recalcificado. Em seguida, foram comparados a esse intervalo de referência os valores obtidos pela análise tromboelastográfica do sangue de seis pacientes com pancreatite recém-diagnosticada. Nos três tipos de reação pelo menos 50% dos pacientes do Grupo Pancreatite apresentaram alterações sugestivas de hipercoagulabilidade. A variável MAXELAST (força máxima do coágulo) foi a que esteve alterada com mais frequência entre os animais doentes. Não houve alteração nos marcadores de velocidade de fibrinólise. Estudos prospectivos que associem outras variáveis de trombose, protocolos de tratamento e prognóstico de pacientes com doenças subjacentes que predisponham à CID são necessários para que se possa afirmar que o traçado obtido pela tromboelastografia realmente representa um estado de hipercoagulabilidade in vivo em pacientes com pancreatite. / Disseminated Intravascular Coagulation (DIC) is a syndrome characterized by systemic activation of blood clotting, leading to diffuse microvascular thrombosis and may compromise multiple organ function. The accelerated consumption of platelets and coagulation factors may, however, originate a state of hypocoagulability, which gives the DIC a paradoxical characteristic in which excess coagulation can lead to a hemorrhagic diathesis. Diseases which cause Systemic Inflammatory Response Syndrome (SIRS) are among the major triggers of DIC, including pancreatitis. The greatest challenge for veterinarians is to diagnose DIC in the early, silent and hypercoagulable phase, since routine laboratory tests, such as platelet count, prothrombin time (PT) and activated partial thromboplastin time (APTT), detect only the state of hypocoagulability, which occurs in the most advanced stage of the syndrome. In this context, thromboelastography analyzers stand out. They are equipment which evaluate coagulation in whole blood and, at least in theory, inform the speed of clot formation, its maximum force and how it dissolves. This is the first study performed in dogs with the ReoRox G2 (MediRox), one of the brands available in the market. Limits of reference were defined from blood analysis of 49 healthy animals for three reaction types: accelerated with tissue factor (TF), accelerated with TF and a platelet aggregation antagonist (abciximab) and with only recalcified blood. Next, values obtained by blood thromboelastographic analysis of six patients with newly diagnosed pancreatitis were compared to this reference range. In all three types of reactions, at least 50% of patients in the Pancreatitis Group presented alterations suggestive of hypercoagulability. The variable MAXELAST (maximum clot strength) was the one that was most frequently altered among ill animals. There was no change in fibrinolysis rate markers. Prospective studies associating other thrombosis variables, treatment protocols, and prognosis of patients with underlying diseases predisposing to DIC are necessary to confirm that the pathway obtained by thromboelastography actually represents a state of hypercoaguability in vivo in patients with pancreatitis.

O Lopap é um ativador de protrombina da lagarta L. obliqua, pertence à família das lipocalinas e apresenta atividade antiapoptótica. O Lopap foi obtido na forma recombinante (rLopap), na levedura P. pastoris, por metodologia escalonável, e sua atividade foi avaliada in vitro e in vivo. O tratamento com rLopap reduziu o tempo de sangramento em animais anticoagulados com enoxaparina. Por outro lado, um peptídeo derivado do Lopap, designado antiapoptotic peptide (AP), foi capaz de induzir a síntese de colágeno em cultura de fibroblastos e na derme de animais. A região correspondente a AP apresentou propriedades físicas e estruturais semelhantes a seqüências relacionadas em outras lipocalinas com atividade antiapoptótica. Estes resultados abrem perspectivas para aplicações do Lopap, como uma molécula procoagulante, e de AP, através de sua ação na modulação celular, como um componente cosmético, no reparo e remodelamento tecidual e em disfunções que envolvem morte celular e perda de colágeno. / Lopap is a prothrombin activator from the L. obliqua caterpillar, belongs to the lipocalin family, and displays antiapoptotic activity. Lopap was obtained in the recombinant form (rLopap) in the P. pastoris yeast, by a scaled up methodology, and its activity was evaluated in vitro and in vivo. Treatment with rLopap reduced the bleeding time in animals anticoagulated with enoxaparin. On the other hand, a Lopap-derived peptide, designated antiapoptotic peptide (AP), was able to induce collagen synthesis in fibroblast culture and in the animal dermis. The region corresponding to AP had similar physical and structural properties when compared with other antiapoptotic lipocalins. These results open perspectives for the use of Lopap, as a procoagulante molecule, and the use of AP, based on its cell modulation effects, as a cosmetic component, aiding tissue repair and in dysfunctions involving cell death and loss of collagen.

As serinoproteases de peçonha de serpentes (SVSPs) agem sobre pontos específicos do sistema circulatório, sendo consideradas promissoras para o tratamento de uma diversidade de desordens hemostáticas. No presente estudo, é descrita a expressão de uma serinoprotease de Crotalus durissus collilineatus (Collineina-1) em Pichia pastoris, bem como a purificação dessa toxina a partir da peçonha de C. d. collilineatus e a caracterização estrutural e enzimática da Collineina-1 nas formas nativa e recombinante. O cDNA que codifica a serinoprotease foi amplificado a partir da biblioteca de cDNA da glândula de peçonha de C. d. collilineatus e ligado ao vetor pPICZ A. A linhagem KM71H de P. pastoris foi transformada com o plasmídeo recombinante e as colônias foram selecionadas por resistência à zeocina. A expressão heteróloga foi realizada em meio mínimo suplementado com metanol, resultando em um rendimento de 56 mg de proteína por litro de cultura. A proteína recombinante foi purificada por um protocolo baseado em técnicas cromatográficas de troca iônica e fase reversa. A purificação da serinoprotease a partir da peçonha de C. d. collilineatus foi realizada pela combinação de técnicas de cromatografia de exclusão molecular, troca iônica e fase reversa, e resultou no isolamento de duas isoformas, denominadas Collineina-1 e 2. Quando analisada por espectrometria de massas, a Collineina-1 recombinante apresentou massa molar de 28.868 Da, enquanto as enzimas Collineina-1 e 2 apresentaram massas de 29.475 Da e 29.388 Da, respectivamente. A partir do alinhamento das sequências parciais das serinoproteases, foi possível determinar 100% de identidade dos aminoácidos para a Collineina-1 nativa e recombinante. O alinhamento múltiplo da sequência deduzida de aminoácidos da Collineina-1 indica uma semelhança estrutural dessa proteína com outras serinoproteases de peçonha de serpente. As enzimas nativa e recombinante mostraram efeitos similares sobre fibrinogênio bovino por clivarem preferencialmente a cadeia A do fibrinogênio, liberando o fibrinopeptídeo A. Ambas as enzimas induziram a coagulação do plasma bovino de forma dose-dependente, sendo que a Collineina-1 recombinante apresentou maior potencial coagulante, com uma dose mínima coagulante (DMC) de 0,08 mg/uL contra 0,225 mgu/L para a proteína nativa. As serinoproteases foram capazes de hidrolisar os substratos cromogênicos S-2222, S-2238 e S2302, embora ambas as enzimas tenham demonstrado maior atividade sobre o substrato S-2302. A atividade esterásica sobre o TAME foi avaliada em diferentes condições de temperatura e na presença de íons divalentes. As duas enzimas demonstraram alta termoestabilidade e tiveram a atividade inibida na presença dos íons Zn2+ e Cu2+. A cinética enzimática de ambas as serinoproteases seguiram o modelo de Michaelis-Menten. A Collineina-1 nativa apresentou um valor de Km de 1,43 mM, contra 1,682 mM para a proteína recombinante, indicando que a proteína nativa apresenta maior afinidade pelo substrato TAME. No entanto, as enzimas apresentaram valores similares de Kcat/Km (250,69 mM.min-1 para a Collineina-1 e 248,03 mM.min-1 para a rCollineina-1), sugerindo que as serinoproteases não diferem significativamente na eficiência em hidrolisar o substrato. Estes resultados demonstraram a adequação do sistema de escolha na produção heteróloga da Collineina-1, já que a proteína recombinante foi expressa com integridade funcional sobre os parâmetros avaliados. / Snake venom serine proteases (SVSPs) act on specific points of the circulatory system and are promising for the treatment of a variety of hemostatic disorders. In the present study, we describe the expression of a serine protease from Crotalus durissus collilineatus (Collineina- 1) in Pichia pastoris, the purification of the native toxin from C. d. collilineatus venom and the structural and enzymatic characterization of Collineina-1 in native and recombinant forms. The cDNA encoding the serine protease was amplified from cDNA library of C. d. collilineatus venom gland and cloned into pPICZ A vector. KM71H P. pastoris strain was transformed with the recombinant plasmid and colonies were selected by zeocin resistance. Heterologous expression was carried out in minimal medium supplemented with methanol, resulting in a yield of 56 mg of protein per liter of culture. The recombinant protein was purified by ion exchange and reverse phase chromatography. Purification of the native serine protease was accomplished by combining techniques of molecular exclusion, ion exchange and reversed phase, and resulted in the isolation of two isoforms, named Collineina-1 and 2. When analyzed by mass spectrometry, the recombinant Collineina-1 showed a molar mass of 28,868 Da, while Collineina-1 and 2 presented masses of 29,475 and 29,388 Da, respectively. The alignment of partial sequences of the enzymes resulted in 100% of amino acid identity between native and recombinant Collineina-1. The multiple alignment of deduced amino acid sequence of Collineina-1 indicates structural similarity with other snake venom serine proteases. The native and recombinant forms of the enzyme showed similar effects on bovine fibrinogen by cleaving preferentially A chain, releasing fibrinopeptide A. Both enzymes induced coagulation of bovine plasma in a dose-dependent way, though recombinant Collineina-1 presented a higher coagulant potential, with a minimum coagulant dose (MCD) of 0.08 mg/uL against 0.225 mg/uL for the native form. The serine proteases hydrolyzed S- 2222, S-2238 and S2302 chromogenic substrates, although both enzymes demonstrated increased activity upon S-2302. The esterase activity on TAME was evaluated at different temperatures and in the presence of divalent ions. Both enzymes showed high thermostability and their activity were inhibited in the presence of Zn2+ and Cu2+. The enzyme kinetics of both serine proteases followed Michaelis-Menten model. The native Collineina-1 showed a Km value of 1.43 mM, against 1.682 mM for the recombinant form, indicating that the native protein has a higher affinity for TAME substrate. However, enzymes had similar values for Kcat/Km (250.69 mM.min-1 for Collineina-1 and 248.03 mM.min-1 for rCollineina-1), suggesting that the serine proteases did not differ significantly in the efficiency to hydrolyze the substrate. These results demonstrated the adequacy of the system of choice in producing the snake venom serine protease, since the recombinant protein was expressed with functional integrity on the evaluated parameters.

Preeclampsia results from incomplete trophoblast invasion of the spiral arteries during early pregnancy. Vascular endothelial growth factor (VEGF) and plasminogen activator inhibitor-1 (PAI-1) are critical factors involved in angiogenesis, invasion and hemostasis at the maternal-fetal interface. Both factors are transcriptionally regulated by hypoxia inducible factor (HIF), a heterodimeric complex consisting of HIF-1[beta] and either HIF-1[alpha] or -2[alpha] whose specificity or redundancy in gene regulation is cell-type specific. This study uses siRNA technology to dissect the mechanisms of hypoxia-mediated regulation of PAI-1 and VEGF expression in first trimester trophoblasts. Immortalized first trimester human extravillous trophoblasts (HTR8/SVneo cells) were maintained in serum-free and serum-containing media for 4h (n=3-4), 8h (n=6), 24h (n=5) and 48h (n=5) under normoxic (21% O2) and hypoxic (1-2% O2) conditions to determine a time of maximum induction of both VEGF and PAI-1. Subsequently, cells were maintained for 48h in the presence or absence of siRNA for HIF-1[alpha], HIF-2[alpha], HIF-1[alpha] + -2[alpha], a non-targeting (NT) sequence or Cyclophilin B (CB). Media were then removed, cells lysed, and Western blotting used to assess HIF-[alpha] knockdown. VEGF and PAI-1 levels in the media were quantified by ELISA and results expressed as pg or ng/[micro]g protein. Results from 3 to 8 independent experiments were analyzed using unpaired t-tests. Under hypoxic conditions treatment of cells with HIF-1[alpha], HIF-2[alpha] or HIF -1[alpha] + -2[alpha] siRNA resulted in >90% HIF-Ñ protein knockdown as determined by Western blotting. 48h of hypoxic treatment caused a statistically significant increase in PAI-1 levels (p<0.01) and VEGF levels (p<0.001) compared to normoxic controls. Under hypoxic conditions, PAI-1 levels were 4.75 [plus-minus] 0.46 ng/[micro]g protein and VEGF levels were 7.27 [plus-minus] 1.08 pg/[micro]g protein. Treatment with siRNA to HIF-1[alpha], HIF-2[alpha] and HIF-1[alpha] + -2[alpha] significantly reduced PAI-1 levels to 3.3 [plus-minus] 0.35 (p<0.02), 3.1 [plus-minus] 0.38 (p<0.03) and 2.4 [plus-minus] 0.19 (p<0.003), respectively. No significant difference in PAI-1 reduction was noted between the three HIF siRNA conditions. Under hypoxic conditions, levels of VEGF in cells treated with siRNA to HIF-1[alpha] (5.79 [plus-minus] 0.55), HIF-2[alpha] (5.50 [plus-minus] 1.24) and HIF-1[alpha] + -2[alpha] (4.24 [plus-minus] 0.93) were reduced compared to the hypoxic control (7.27 [plus-minus] 1.08), yet these effects did not reach statistical significance. However, when compared with the levels observed in cells treated with NT siRNA (9.90 [plus-minus] .98), all HIF siRNA treatments promoted a significant reduction in VEGF expression (p<0.003, p<0.02 and p<0.003 for HIF-1[alpha], HIF-2[alpha] and HIF-1[alpha]+ -2[alpha], respectively). In conclusion, these results indicate that hypoxia-mediated changes in PAI-1 and VEGF expression in trophoblasts are regulated similarly by both HIF-1[alpha] and HIF-2[alpha]. This provides important insight into the molecular mechanisms regulating hemostasis and trophoblast invasion as well as their potential dysfunction in pregnancies complicated by preeclampsia

Hydroxyethyl starches (HES) are the most routinely used synthetic colloids during fluid resuscitation and have reported effects on coagulation. The overall goal of the investigation in this thesis was to evaluate the effects of tetrastarch administration on hemodynamic, laboratory, and hemostatic variables in healthy dogs and dogs with systemic inflammation. The objectives were to compare hemodynamic and laboratory variables in dogs receiving an isotonic crystalloid (0.9% NaCl) or tetrastarch during health and after induction of systemic inflammation; to compare the hemostatic effects of an isotonic crystalloid (0.9% NaCl) and synthetic colloid (tetrastarch) in healthy dogs and dogs with induced systemic inflammation; to compare two different protocols for TEG® activation and to determine the correlation between TEG® variables and traditional coagulation test results. Sixteen adult purpose-bred Beagles were randomized into one of two groups receiving fluid resuscitation with either 40 mL/kg IV isotonic crystalloid (0.9% NaCl) or synthetic colloid (tetrastarch) after administration of lipopolysaccharide (LPS; 5 μg/kg, IV) or an equal volume of placebo (0.9% NaCl, IV). Blood samples, for analysis, were collected at 0, 1, 2, 4, and 24 hours from the time of fluid resuscitation. After a 14-day washout period, the study was repeated such that dogs received the opposite treatment (LPS or placebo) and the same resuscitation fluid. Resuscitation with equal volumes of 0.9% NaCl and tetrastarch caused similar changes in hemodynamic and laboratory variables in dogs with LPS-induced systemic inflammation; however, larger increases in HR and blood pressure were seen within the first 2 hours following tetrastarch administration compared to 0.9% NaCl. Tetrastarch administration increased COP in all dogs, despite a decrease in TS. Tetrastarch bolus administration to dogs with LPS-induced systemic inflammation also resulted in a transient hypocoagulability characterized by a prolonged PTT, decreased clot formation speed and clot strength, and acquired type 1 von Willebrand disease. Considering the limited additional benefit of tetrastarch administration on hemodynamic variables demonstrated, as well as the transient adverse hemostatic effects of tetrastarch administration, the increased cost associated with the use of tetrastarch likely negates its use as a first line treatment during fluid resuscitation in dogs. / Pet Trust Fund

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 6 uppsatser.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this experiment was to document the postoperative evolution of New Zealand rabbits that underwent a hemi laminectomy surgery (T13-L1) and received a graft of autogenous muscle as an hemostatic agent into the spinal canal. These animals were followed for a period of 14 and 28 days with daily neurological assessments and, at the end of their follow-up period, were euthanized in order to remove the graft site to be examined microscopically. The animals were divided into 6 groups such as the control group A and B, C and D treated with 25% decrease of the medullary canal and, E and F treated with 50% decrease of the medullary canal. All groups were evaluated neurologically every day until euthanasia. Groups A, C and E were euthanized at 14 days after the surgery and groups B, D and F at 28 days. The segments T11-L3 vertebral column of all the rabbits were collected and sent for histopathological examination. In order to evaluate the neurological postoperative effect, the animals were classified daily by the Tarlov scale and the results were compared by nonparametric Kruskal-Wallis test for each time (days). There was no statistical difference among the groups. Histopathological examination showed the presence of muscle grafted in the spinal canal and the spinal cord compression caused by the graft. / A hemorragia é uma preocupação importante em pacientes submetidos a intervenção cirúrgica descompressiva da medula espinhal ou de estabilização na coluna vertebral. O objetivo desse experimento foi documentar a evolução pós-operatória de coelhos Nova Zelândia que sofreram hemilaminectomia (T13-L1) e receberam um segmento de músculo autógeno como agente hemostático dentro do canal vertebral. Os animais foram separados em seis grupos sendo os grupos A e B controle, C e D tratados com diminuição de 25% do canal medular e E e F tratados com diminuição de 50% do canal medular. Todos os coelhos tiveram avaliação neurológica diária até a eutanásia. Aqueles dos grupos A, C e E sofreram eutanásia aos 14 dias de pós-operatório e os demais (B, D e E) aos 28 dias. Os segmentos T11-L3 da coluna vertebral contendo a medula espinhal de todos os coelhos foram coletados e enviados para exame histopatológico. Para avaliação neurológica no pós-operatório, os animais foram classificados diariamente pela escala de Tarlov e os resultados foram comparados entre eles pelo teste não paramétrico de Kruskal-Wallis para cada tempo (dia). Não houve diferença estatística da avaliação neurológica entre os grupos estudados. O exame histopatológico demonstrou a presença do músculo transplantado no canal vertebral e a compressão da medula espinhal provocada pelo enxerto.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / This study evaluated the use of bipolar electrosurgery and laparoscopic clip applier with respect to surgical time, blood loss and inflammatory response during video-assisted ovariohysterectomy with two portals. Two groups (n=10) assessed each of the hemostatic techniques during castration and a third group (GIII, n=6) evaluated changes in serum promoted only by the clinical and anesthetic protocols used in order to exclude the changes made by them. The surgical times, such as the volume of blood loss were significantly lower in Bipolar Group. The inflammatory response was significantly higher throughout the evaluation period after surgery, but no clinical manifestations different than those presented by the Clipador Group. There were no significant changes in packed cell volume between the groups, but among the times evaluated it reduced about 10% from initial value until four hours after the procedure, in the surgical groups and Group III. Both techniques have good execution by the video-assisted procedure, however, the use of bipolar forceps allows minor surgical times, minimal blood loss and shorter learning curve for the surgeon. The bleeding does not result in physiological changes and that one s on packed cell volume are presented because of the clinical and anesthetic protocols. / Este estudo avaliou a utilização da eletrocirurgia bipolar e do clipador laparoscópico em relação ao tempo cirúrgico, perda sanguínea e resposta inflamatória durante a ovariohisterectomia videoassistida com dois portais. Dois grupos (n=10) avaliaram cada uma das técnicas hemostáticas durante as castrações e um grupo (GIII, n=6) avaliou as alterações séricas promovidas somente pelo protocolo clínico e anestésico utilizado, a fim de excluir as alterações promovidas por estes. O tempo cirúrgico, assim como o volume de sangue perdido foram significativamente menores no Grupo Bipolar. A resposta inflamatória apresentou valores significativamente maiores durante todo o período de avaliação pósoperatório, sem manifestações clínicas diferentes das apresentadas pelo Grupo Clipador. Em relação ao hematócrito não houve alterações significativas entre os grupos, mas entre os tempos de avaliação reduziu cerca de 10% do valor inicial, até quatro horas do final do procedimento, tanto nos grupos cirúrgicos como no Grupo III. Ambas as técnicas são de boa execução através do procedimento videoassistido, porém, o uso da pinça bipolar permite menores tempos cirúrgicos, sangramento mínimo e menor curva de aprendizado do cirurgião. O sangramento não acarreta em alterações fisiológicas e as mudanças apresentadas no hematócrito são provenientes dos protocolos clínico e anestésico instituídos.

Made available in DSpace on 2014-06-11T19:23:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-12-17Bitstream added on 2014-06-13T20:50:50Z : No. of bitstreams: 1 almeidajunior_p_me_araca.pdf: 2659878 bytes, checksum: 7b05cfcaf4408ab253ef351ae3eb5826 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A hemorragia após extração dental constitui-se em uma das complicações mais freqüentes na prática da cirurgia oral. Devido à dificuldade para se exercer manobras como pinçamentos e ligaduras de vasos neste tipo de hemorragias, existe a possibilidade do preenchimento do alvéolo com materiais hemostáticos de ação tópica. O propósito deste estudo foi analisar a influência de três hemostáticos tópicos (Hemostop®, Pro Tape® e ViscoStat®) na cronologia do processo de reparo em feridas de extração dental por meio de uma análise histológica e histométrica. Para tanto foram utilizados 60 ratos (Wistar) machos divididos em quatro grupos de 15 animais cada. Todos os animais foram submetidos à extração do incisivo central superior direito, seguido ou não da colocação de agente hemostático entre o terço médio e apical do alvéolo dental, e posterior sutura com fio reabsorvível. Em grupos de cinco, os animais foram sacrificados aos 7, 14 e 28 dias pós-operatórios por inalação excessiva de éter sulfúrico. Suas maxilas foram separadas, fixadas em formalina, descalcificadas em EDTA e incluídas em parafina. Foram realizados cortes de 6 æm de espessura e corados com Hematoxilina e Eosina, e Tricrômio de Masson. Após a análise histológica, em microscópio óptico; e histometria óssea, com o software ImageLab, os resultados foram submetidos ao teste não-paramétrico de Kruskal-Wallis. Pela metodologia aplicada foi possível concluir que: 1) houve atraso na cronologia do processo de reparo alveolar em todos os grupos tratados; 2) os materiais analisados provocaram intensa reação inflamatória no tecido adjacente; 3) em todos os períodos estudados (7, 14 e 28 dias), a análise histométrica revelou maior neoformação óssea nos animais do grupo 1 (controle). No entanto, a análise estatística constatou diferença significante (p<0,05) somente no 70 dia,... / The hemorrhage after dental extraction is one of the most frequent complications in practice of the oral surgery. Due to the difficulty to exercise maneuvers as arrestty and ligature of blood vessel in this type of hemorrhages, exists the possibility of the filling of the alveolus with hemostatics materials of topical action. The purpose of this study was to analyze the influence of three topical hemostatics (Hemostop®, Pro Tape® and ViscoStat®) in the chronology of the repair process in wounds of dental extraction through a histologic and histometric analysis. For such, 60 male's rats (Wistar) were used divided in four groups of 15 animals each. All the animals were submitted to the extraction of the right superior central incisor, followed or not of the placement of hemostatics agent among the medium and apical third of the dental alveolus, and subsequent suture with reabsorble filament. In groups of five, the animals were sacrificed to the 7, 14 and 28 postoperative days by excessive inhalation of sulfuric ether. Your maxillaries were separate, fixed in formalin solution, decalcified in EDTA and included in paraffin. Cuts of 6 æm of thickness were accomplished and stained with hematoxylin and eosin, and Masson's trichromic. After the histologic analysis, in optical microscope; and histometric bony, with the software ImageLab, the results were submitted to the no-parametric test of Kruskal-Wallis. For the applied methodology it was possible conclude that: 1) there was delay in the chronology of the alveolar repair process in all the treated groups; 2) the analyzed materials instigated a intense inflammatory reaction in the adjacent tissue; 3) in all the studied periods (7, 14 and 28 days), the histometric analysis revealed larger bony neoformation in the animals of the group 1 (control group)...(Complete abstract click electronic access below)