Background Several case reports and studies have alluded to an increased prevalence of venous thrombosis in human immunodeficiency virus positive (HIV-positive) patients. Although a relationship between HIV infection and thrombotic disease has been suggested, the mechanisms predisposing to thrombosis have not been fully elucidated. Aim A prospective study, to determine possible coagulation factor abnormalities that could explain the predisposition to thrombosis in HIV-infected African (Black) patients, was undertaken. Method African (Black) patients, with acute upper segment deep vein thrombosis (DVT) confirmed by duplex ultrasound, were enrolled. Patients who had recognisable risk factors such as recent surgery, pregnancy or malignancy, were excluded. After informed consent, blood samples were taken for baseline tests as well as a thrombophilia screen. The control group comprised known HIV-positive African (Black) patients without DVT. Patients with DVT who were found to be HIV-negative were also analysed. Analysis was done in 2 parts: HIV-positive patients with and without thrombosis and HIV-positive and negative patients with thrombosis were compared. Results Part A: HIV-positive patients with and without thrombosis Of the 77 patients with DVT, 50 patients tested HIV-positive. These 50 patients (HIV-positive DVT-arm), as well as 56 controls (HIV-positive, no DVT), were enrolled into the study. The groups were well matched with regard to age, sex and cluster designation 4 (CD4) count. On univariate analysis, significant findings in the DVT-arm were a history of active tuberculosis on treatment, low protein C levels and a positive qualitative D-dimer, whereas on multivariate analysis, only tuberculosis and an elevated D-dimer proved to be significant. Part B: HIV-positive and negative patients with thrombosis There were 20 HIV-negative patients with DVT who met our inclusion criteria Limited assessment was done on this group owing to unavailability of some data. The mean age of the HIV positive DVT group was significantly lower than the HIV-negative group with DVT (31.78 vs. 41.45 years; p=0.005). There was no significant difference in the prevalence of tuberculosis between the HIV-positive and HIV-negative patients with thrombosis (p = 0.269). Mean protein C levels were reduced in the HIV-positive group and normal in the HIV-negative group. They were significantly lower in the HIV-positive patients compared to the negative group (p=0.02). Conclusion The findings of the study suggest a relationship between HIV, its complications and DVT. Although this study confirms HIV infection as a risk factor for thrombosis, clear pathogenetic mechanisms remain to be elucidated. In our population, tuberculosis appears to be an important risk factor predisposing patients to the development of DVT, both in the HIVpositive and negative population. Further studies will need to be done to confirm this hypothesis. / Thesis (MMed)-University of KwaZulu-Natal, Durban, 2006.

The purpose of this study was to characterize the association between anti-prothrombin antibodies and the lupus anticoagulant (LA) in order to elucidate the antigenic site of the LA. Plasma from 8 patients with the LA had evidence of anti-prothrombin antibodies on prothrombin crossed immunoelectrophoresis as characterized by material moving slower in the first dimension of electrophoresis than normal prothrombin, i.e., a trailing shoulder. Four of 5 LA patients with a prolonged prothrombin time demonstrated the most pronounced evidence of anti-prothrombin antibodies. All patients were shown to have an essentially normal level of prothrombin antigen. Using an enzyme-linked immunosorbent assay (ELISA), six of 8 LA patients tested positive for anticardiolipin antibodies (aCL) of the IgG isotype while 7 of 8 LA patients tested positive for antiphosphatidylserine antibodies (aPS) of the IgG isotype.An anti-human Factor II (prothrombin) ELISA was developed to confirm the presence of anti-Factor II (aFII) activity in LA patients. Seven of 8 LA patients were positive for aFII activity. A strong parallel existed between the presence of aPS activity, anti-human Factor II activity, and the LA, i.e., 7 of 8 LA plasmas were aPS (+)/aFII (+). An antibovine Factor II ELISA was developed to determine if the aFII activity associated with LA patients is speciesspecific. Three of 5 LA patients positive for anti-human Factor II activity were also shown to be positive for antibovine Factor II activity. Antibodies with specificity for human prothrombin were purified from LA plasmas using a prothrombin affinity column. Three of 8 LA patient eluates were shown to be positive for aPS (IgG) while none were positive for aCL (IgG or IgM) or human aFII activity. Affinity-purified eluates were assayed for LA activity using the dilute Russell viper venom time (dRVVT). None of the LA patient eluates were shown to prolong the dRVVT when present with normal plasma in concentrations up to 100 micrograms/mL. / Department of Chemistry

Diss. (sammanfattning) Uppsala : Univ., 2003. / Härtill 4 uppsatser.

Thesis (Ph.D.)--Cleveland State University, 2008. / Abstract. Title from PDF t.p. (viewed on Oct. 8, 2008). Includes bibliographical references. Available online via the OhioLINK ETD Center. Also available in print.

Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 275-317).

Thesis (M.S.)--Georgia State University, 2005. / Title from title screen. Roberta Attanasio, committee chair; P.C. Tai, W.C. Hooper, committee members. Electronic text (57 p. : col. ill.) : digital, PDF file. Description based on contents viewed Aug. 15, 2007. Includes bibliographical references (p. 55-57).

VIANA, Carolina de Araújo. Caracterização bioquímica da atividade pró-coagulante de proteases de fluidos laticíferos. 2011. 119 f. Dissertação (mestrado em bioquímica)- Universidade Federal do Ceará, Fortaleza-CE, 2011. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-03-31T18:14:07Z No. of bitstreams: 1 2016_dis_caviana.pdf: 8725116 bytes, checksum: 767aa06f3d14be0e807d03f424c5c370 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-18T19:57:06Z (GMT) No. of bitstreams: 1 2016_dis_caviana.pdf: 8725116 bytes, checksum: 767aa06f3d14be0e807d03f424c5c370 (MD5) / Made available in DSpace on 2016-05-18T19:57:06Z (GMT). No. of bitstreams: 1 2016_dis_caviana.pdf: 8725116 bytes, checksum: 767aa06f3d14be0e807d03f424c5c370 (MD5) Previous issue date: 2011 / Latex proteases have grown in attention because of their ability to exhibit both thrombin and plasmin-like effects. In this study, the plant latex proteins Calotropis procera (CpLP), Cryptostegia grandiflora (CgLP) and Plumeria rubra (PrLP) were investigated in terms of these activities. For both samples were investigated for their fibrinogenolytic and fibrinolytic activity in human plasma and by incubation with human fibrinogen by measuring the clotting time, electrophoretic or spectrophotometric assays and diffusion in agarose gel. In vivo effect of CpLP on clot formation of plasma of healthy and septic mice that have been experimentally infected with Salmonella enterica serovar Typhimurium was also studied. Groups of five mice were treated with CpLP (30 mg/Kg), S. enterica (107 CFU/mL) or CpLP 24 h prior bacteria. After sacrificing animals, blood samples were examined for coagulation time, platelet content and protein profile. The protein fractions of C. procera exhibiting proteolytic activity were capable to hydrolyze fibrinogen similar to thrombin, while the protein fractions of Cr. grandiflora exhibiting proteolytic activity were capable to hydrolyze fibrinogen similar to plasmin. The samples exhibited fibrinogenolytic activity in a dose and time manner, but were not able to dissolve the fibrin clot. Procoagulant activity was eliminated by inhibition of latex proteases with cysteine proteinase inhibitor E-64. Pepstatin, PMSF and EDTA were not inhibitory. Time of clot formation of plasma in septic mice and platelet content were consistently reduced as compared to healthy animals. CpLP exhibited antagonistic effects. It statistically reversed the effects of sepsis on clot-time formation associated to preservation on platelet content. However, CpLP exhibited opposite effect on non-septic mice, inducing faster clot formation, compared to healthy animals but without changing platelet content. Results reported in this work confirm fibrinogenolytic activity associated to cysteine proteases of latex and show a very intriguing in vivo protective activity of CpLP on platelet content on septic animals with apparent benefit effect against disseminated vascular coagulation, a pivotal event associated to lethal sepsis. This effect was however not observed when CpLP was given to healthy animals. / As proteases de látex têm atraído atenção devido à habilidade de exibir atividades semelhantes à trombina e à plasmina. Neste estudo, as proteínas do látex das plantas Calotropis procera (CpPL), Cryptostegia grandiflora (CgPL) e Plumeria rubra (PrPL) foram avaliadas em termos destas atividades. Para tanto, as amostras foram investigadas quanto as suas atividades fibrinogenolíticas e fibrinolíticas, em plasma humano e por incubação com fibrinogênio humano através da medida do tempo de coagulação, ensaios eletroforéticos, espectrofotométricos, ou de difusão em gel de agarose. O efeito de CpPL in vivo, sobre o tempo de coagulação no plasma de camundongos saudáveis ou sépticos, que foram experimentalmente infectados com a bactéria Salmonella enterica sorotipo Typhimurium, também foi estudado. Grupos de cinco camundongos foram tratados com CpPL (30 mg/Kg), S. enterica (107 UFC/mL) ou CpPL 24 h antes da inoculação bacteriana. Depois do sacrifício dos animais, as amostras de sangue foram examinadas quanto ao tempo de coagulação, conteúdo de plaquetas e perfil protéico. As frações protéicas de C. procera exibindo atividade proteolítica foram capazes de hidrolisar o fibrinogênio de forma similar à trombina, enquanto que as frações protéicas de Cr. grandiflora exibindo atividade proteolítica foram capazes de hidrolisar o fibrinogênio de forma similar à plasmina. As amostras exibiram atividade fibrinogenolítica de forma dose e tempo dependente, mas não foram capazes de dissolver totalmente o coágulo de fibrina. As atividades fibrinogenolíticas foram eliminadas pela inibição das proteases dos látices com E-64, um inibidor de protease cisteínica. Pepstatina, PMSF e EDTA não se mostraram inibitórios. O tempo de formação do coágulo no plasma de camundongos sépticos e o conteúdo de plaquetas foram consistentemente reduzidos quando comparados aos animais saudáveis. CpPL exibiu efeitos antagonistas. Foi capaz de reverter, estatisticamente, o efeito da sepse no tempo de formação do coágulo associado à preservação do conteúdo de plaquetas. Contudo, CpPL exibiu efeito oposto em camundongos não sépticos, induzindo rápida formação do coágulo, comparado aos animais saudáveis, porém sem alterar o conteúdo de plaquetas. Os resultados relatados neste trabalho confirmam a atividade fibrinogenolítica associada a proteases cisteínicas de látex e mostram uma efeito protetor in vivo muito intrigante de CpPL no conteúdo de plaquetas em animais sépticos, com aparentes efeitos benéficos contra a coagulação intravascular disseminada, um evento crucial associado à sepse letal. Este efeito, porém, não foi observado quando CpPL foi dado aos animais saudáveis.

Made available in DSpace on 2014-12-02T11:16:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-10-08Bitstream added on 2014-12-02T11:21:22Z : No. of bitstreams: 1 000793434.pdf: 2165080 bytes, checksum: 7892c0c8724dc483d7ff334b62d34e3e (MD5) / O presente trabalho teve como objetivo a síntese e a caracterização de diferentes tipos de famílias zeolíticas e a avaliação do uso como agentes hemostáticos coagulantes. Foram sintetizadas três classes de zeólitas: faujasita (FAU), gismondina (GIS) e mordenita (MOR) em sua forma sódica, e estas zeólitas foram convertidas para as formas Ca2+ pelo processo de troca iônica. Após a caracterização desses materiais, foram avaliados seus potenciais como agentes hemostáticos coagulantes, tanto em sua forma sódica como a forma Ca2+, com testes in vitro utilizando a tromboelastografia. Para que se obtivesse dados comparativos, foi utilizado nos testes um agente hemostático já conhecido, o Caolin. Os resultados mostraram que os seis materiais zeolíticos sintetizados agiram como agente hemostático coagulante diminuindo consideravelmente o tempo de coagulação e aumentando a taxa de geração de trombina. Entretanto, a zeólita GIS/Ca2+ exibiu maior eficácia nos parâmetros gerais como taxa de geração do coágulo (K), taxa de geração de trombina (α) e propriedade elástica da fibrina (AM), enquanto que a MOR/Ca2+ exibiu resultados menos eficazes nos parâmetros gerais de coagulação, demostrando que sua estrutura é de difícil acesso ao Ca2+ durante o processo de troca iônica, interferindo no processo de coagulação / The main goals of this research work were the synthesis and characterization of different types of zeolites and evaluation of their use as hemostatic agents. Initially, three differents zeolites were synthesized: faujasite (FAU), gismondine (GIS) and mordenite (MOR). The three zeolites were first prepared in their sodium form and thereafter they were submitted to an ion exchange process in order to the replace extra-framework Ca2+. After characterization these materials, were assessed in their potential as hemostatic agents, both the sodium as weel as the calcium forms, in vitro tests using thromboelastography. In order obtain comparative data was used in testing agent hemostatic already know, the Kaolin. The resultds showed that all six zeolites materials have successfully as a agent hemostatic reducing the coagulation time and increasing the rate of clot thrombin generation. Altrought, zeolite GIS/Ca2+ to be more efficient in general parameters such as rate of generation (K), thrombin generation rates (α) and elastic property of fibrin (AM), while the results showed MOR/Ca2+ less efficient in the general parameters of coagulation, showing that its structure is difficult acess to Ca2+ in the ion exchange process

Orientador: José Geraldo Nery / Banca: Claudia Regina Bonini Domingos / Banca: Moacir Fernandes Godoy / Resumo: O presente trabalho teve como objetivo a síntese e a caracterização de diferentes tipos de famílias zeolíticas e a avaliação do uso como agentes hemostáticos coagulantes. Foram sintetizadas três classes de zeólitas: faujasita (FAU), gismondina (GIS) e mordenita (MOR) em sua forma sódica, e estas zeólitas foram convertidas para as formas Ca2+ pelo processo de troca iônica. Após a caracterização desses materiais, foram avaliados seus potenciais como agentes hemostáticos coagulantes, tanto em sua forma sódica como a forma Ca2+, com testes in vitro utilizando a tromboelastografia. Para que se obtivesse dados comparativos, foi utilizado nos testes um agente hemostático já conhecido, o Caolin. Os resultados mostraram que os seis materiais zeolíticos sintetizados agiram como agente hemostático coagulante diminuindo consideravelmente o tempo de coagulação e aumentando a taxa de geração de trombina. Entretanto, a zeólita GIS/Ca2+ exibiu maior eficácia nos parâmetros gerais como taxa de geração do coágulo (K), taxa de geração de trombina (α) e propriedade elástica da fibrina (AM), enquanto que a MOR/Ca2+ exibiu resultados menos eficazes nos parâmetros gerais de coagulação, demostrando que sua estrutura é de difícil acesso ao Ca2+ durante o processo de troca iônica, interferindo no processo de coagulação / Abstract: The main goals of this research work were the synthesis and characterization of different types of zeolites and evaluation of their use as hemostatic agents. Initially, three differents zeolites were synthesized: faujasite (FAU), gismondine (GIS) and mordenite (MOR). The three zeolites were first prepared in their sodium form and thereafter they were submitted to an ion exchange process in order to the replace extra-framework Ca2+. After characterization these materials, were assessed in their potential as hemostatic agents, both the sodium as weel as the calcium forms, in vitro tests using thromboelastography. In order obtain comparative data was used in testing agent hemostatic already know, the Kaolin. The resultds showed that all six zeolites materials have successfully as a agent hemostatic reducing the coagulation time and increasing the rate of clot thrombin generation. Altrought, zeolite GIS/Ca2+ to be more efficient in general parameters such as rate of generation (K), thrombin generation rates (α) and elastic property of fibrin (AM), while the results showed MOR/Ca2+ less efficient in the general parameters of coagulation, showing that its structure is difficult acess to Ca2+ in the ion exchange process / Mestre

Orientador: Gilberto Di Nucci / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-08T17:30:38Z (GMT). No. of bitstreams: 1 Pereira_Renata_D.pdf: 3731269 bytes, checksum: ef00e8c346cabde2a33e5eea29d6f2c1 (MD5) Previous issue date: 2006 / Resumo: Desde 1986 acidentes causados pelo contato com lagartas de mariposas da espécie Lonomia obliqua vêm sendo notificados na Região Sul do Brasil. O envenenamento humano por esta espécie resulta em alterações do sistema de coagulação, caracterizando um quadro de coagulação intravascular disseminada, associado a uma síndrome fibrinolítica severa. Estudos demonstraram que o veneno da Lonomia obliqua contém um ativador de fator X e um ativador de protrombina. Uma proteína ativadora de protrombina, denominada LOPAP (¿Lonomia obliqua prothrombin activator protease¿) foi isolada e caracterizada bioquímica e fisiologicamente. Esta enzima é uma serino protease de 69 kDa. Quando testada in vivo, a LOPAP leva à formação de microcoágulos, hemorragia microvascular e pulmonar, sangue incoagulável e uma infiltração leucocitária pulmonar em ratos. Neste trabalho, através de cromatografia de exclusão, seguida por cromatografia de fase reversa (HPLC) isolou-se uma proteína de 20745.7 Da do extrato de cerdas de L. obliqua. Durante o processo, foi avaliada a atividade ativadora de fator X humano purificado in vitro, através de ensaio de cinética enzimática com o uso de substratos cromogênicos. A proteína ativa isolada apresentou imunorreatividade com o soro-antilonômico, produzido pelo Instituto Butantan. Com o uso de técnicas aplicadas a proteômica, determinou-se a seqüência de aminoácidos da proteína com atividade tipo fator Xa. Trata-se de uma proteína nova, ainda não seqüenciada, a qual apresenta grande identidade com proteínas da família das lipocalinas / Abstract: Since 1986 accidents caused by contact with caterpillars of butterflies of the Lonomia obliqua species comes being notified in the South Region of Brazil. The human envenoming for this species results in alterations of the coagulation system, characterizing a disseminated intravascular coagulation, associated to a severe fibrinolytic syndrome. Studies had demonstrated that the venom of the Lonomia obliqua contains a factor X and a prothrombin activator. An activator protein of prothrombin, called LOPAP (¿Lonomia obliqua prothrombin activator protease¿) was isolated and biochemist and physiologically characterized. This enzyme is a serine protease of 69 kDa. When tested in vivo, the LOPAP leads to thrombus formation, microvasculary and pulmonary hemorrhage, unclottable blood and leukocyte infiltration in the lungs at rats. In this work, through chromatography of exclusion, followed by phase reverse chromatography (HPLC), it was isolated a 20745.7 Da protein of the spicules extract of L. obliqua. During the process, it was evaluated the purified human factor X activator activity in vitro, through kinetic assay with the chromogenic substrate use. The isolated protein presented factor Xa like activity and presented immunorreactivity with the antilonomic serum, produced by Butantan Institute. Using techniques applied to the proteomic studies, it was determined the amino acid sequence of the protein with factor Xa like activity. It is a new protein, not yet sequenced, which has large identity with lipocalins family protein / Doutorado / Doutor em Farmacologia