RESUMO
INTRODUCTION: Thrombosis is one of the leading causes of morbidity and mortality worldwide. Venous thromboembolic disease (VTD) is considered a new epidemic. FXII deficiency is supposed to be a cause of thrombosis. To search for unknown causes of thrombosis in our population, our aim was to determine if FXII deficiency can be considered a risk factor for VTD. METHODS: Young adult Mexican patients with at least one VTD episode and healthy controls were included in this prospective, observational, controlled study. Liver and renal function tests, blood cytometry, and blood coagulation assays were performed. Plasma FXII activity and its concentration were evaluated. RESULTS: Over a two-year period, 250 patients and 250 controls were included. FXII activity was significantly lower in the control group compared to patients with VTD (p = 0.005). However, percentage of patients and controls with FXII deficiency was 8.8 and 9.2%, respectively (p = 1.000). No significant association was found between FXII deficiency and VTD (p = 1.0). FXII plasma concentration was lower in controls vs. patients with VTD: 4.05 vs. 6.19 ng/mL (p <0.001). Percentage of patients with low FXII plasma concentration was 1.6% and 6.0% in patients and controls, respectively (p = 0.010). CONCLUSIONS: FXII deficiency is a frequent finding in patients with VTD and controls in Mexico. Some patients with FXII deficiency had normal APTT result, an effect not described above. FXII plasma concentration was lower in patients with low activity.
Assuntos
Deficiência do Fator XII , Trombose , Humanos , Adulto Jovem , Deficiência do Fator XII/complicações , Deficiência do Fator XII/epidemiologia , México/epidemiologia , Prevalência , Estudos Prospectivos , Fator XII/metabolismoRESUMO
Ultrasmall gold nanoparticles (usNPs) and nanoclusters are an emerging class of nanomaterials exhibiting distinctive physicochemical properties and in vivo behaviors. Although understanding the interactions of usNPs with blood components is of fundamental importance to advance their clinical translation, currently, little is known about the way that usNPs interact with the hemostatic system. This study describes the effects of a model anionic p-mercaptobenzoic acid-coated usNP on the coagulation cascade, with particular emphasis on the contact pathway. It is found that in a purified system, the anionic usNPs bind to and activate factor XII (FXII). The formed usNP-FXII complexes are short-lived (residence time of â¼10 s) and characterized by an affinity constant of â¼200 nM. In human plasma, the anionic usNPs activate the contact pathway and promote coagulation. The usNPs also exhibit anticoagulant activity in plasma by interfering with the thrombin-mediated cleavage of fibrinogen. Taken together, these findings establish that anionic usNPs can disturb the normal hemostatic balance, which in turn may hinder their clinical translation. Finally, it is shown that usNPs can be designed to be nearly inert in plasma by surface coating with the natural peptide glutathione.
Assuntos
Hemostáticos , Nanopartículas Metálicas , Anticoagulantes/farmacologia , Fator XII/química , Fator XII/metabolismo , Fibrinogênio , Glutationa , Ouro/química , Ouro/farmacologia , Humanos , Nanopartículas Metálicas/química , Trombina/metabolismoRESUMO
Angioedema is a prevailing symptom in different diseases, frequently occurring in the presence of urticaria. Recurrent angioedema without urticaria (AE) can be hereditary (HAE) and acquired (AAE), and several subtypes can be distinguished, although clinical presentation is quite similar in some of them. They present with subcutaneous and mucosal swellings, affecting extremities, face, genitals, bowels, and upper airways. AE is commonly misdiagnosed due to restricted access and availability of appropriate laboratorial tests. HAE with C1 inhibitor defect is associated with quantitative and/or functional deficiency. Although bradykinin-mediated disease results mainly from disturbance in the kallikrein-kinin system, traditionally complement evaluation has been used for diagnosis. Diagnosis is established by nephelometry, turbidimetry, or radial immunodiffusion for quantitative measurement of C1 inhibitor, and chromogenic assay or ELISA has been used for functional C1-INH analysis. Wrong handling of the samples can lead to misdiagnosis and, consequently, mistaken inappropriate approaches. Dried blood spot (DBS) tests have been used for decades in newborn screening for certain metabolic diseases, and there has been growing interest in their use for other congenital conditions. Recently, DBS is now proposed as an efficient tool to diagnose HAE with C1 inhibitor deficiency, and its use would improve the access to outbound areas and family members. Regarding HAE with normal C1 inhibitor, complement assays' results are normal and the genetic sequencing of target genes, such as exon 9 of F12 and PLG, is the only available method. New methods to measure cleaved high-molecular-weight kininogen and activated plasma kallikrein have emerged as potential biochemical tests to identify bradykinin-mediated angioedema. Validated biomarkers of kallikrein-kinin system activation could be helpful in differentiating mechanisms of angioedema. Our aim is to focus on the capability to differentiate histaminergic AE from bradykinin-mediated AE. In addition, we will describe the challenges developing specific tests like direct bradykinin measurements. The need for quality tests to improve the diagnosis is well represented by the variability of results in functional assays.
Assuntos
Angioedema/diagnóstico , Angioedemas Hereditários/diagnóstico , Erros de Diagnóstico/prevenção & controle , Angioedema/sangue , Angioedema/imunologia , Angioedemas Hereditários/sangue , Angioedemas Hereditários/genética , Angioedemas Hereditários/imunologia , Biomarcadores/sangue , Biomarcadores/metabolismo , Bradicinina/sangue , Bradicinina/imunologia , Bradicinina/metabolismo , Proteína Inibidora do Complemento C1/análise , Proteína Inibidora do Complemento C1/genética , Proteína Inibidora do Complemento C1/metabolismo , Análise Mutacional de DNA , Diagnóstico Diferencial , Teste em Amostras de Sangue Seco/métodos , Ensaio de Imunoadsorção Enzimática , Fator XII/genética , Humanos , Mutação , Plasminogênio/genética , RecidivaRESUMO
Hereditary angioedema (HAE) is an autosomal dominant disease mostly due to the deficiency of C1 inhibitor (C1-INH). HAE with normal C1-INH was first described in 2000 and associated with mutations in the coagulation factor XII in 2006. Both diseases are associated with high bradykinin production, resulting in increased vascular permeability. Gastrointestinal edema due to HAE can be misdiagnosed as acute abdomen and unnecessary surgical procedures may be performed. The present study evaluates the prevalence of surgical procedures and/or acute abdomen in HAE patients with the coagulation factor XII mutation. It is a retrospective study where patients were diagnosed with recurrent angioedema without urticaria, normal C1-INH levels, and positive family history of angioedema. All patients were evaluated for the known mutations located at exon 9 of the F12 gene. Medical records were evaluated and questionnaires were applied to 52 patients with normal C1-INH levels (age range 13-76 years; 47/52, 90.38% women; 5/52, 9.61% men). F12 mutation was present in 32/52 patients (61.5%). Acute abdominal pain was diagnosed in 16/52 (30.76%) patients, appendicitis in 9/16 (56.2%), and undetermined diagnosis in 7/16 (43.7%). Among patients diagnosed with acute abdominal pain, 13/16 (81.2%) underwent surgery and 3/16 (18.7%) improved without surgical intervention. We conclude that many HAE patients with coagulation factor XII mutation were misdiagnosed with acute abdomen and subjected to unnecessary invasive procedures. It is critical to disseminate information about this rare mutation in patients with otherwise normal C1-INH activity, in order to speed up diagnosis and avoid misconduct.
Assuntos
Abdome Agudo , Angioedema , Angioedemas Hereditários , Dor Abdominal , Adolescente , Adulto , Idoso , Angioedemas Hereditários/diagnóstico , Angioedemas Hereditários/genética , Proteína Inibidora do Complemento C1 , Fator XII/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
Alzheimer disease (AD) is the most common form of dementia in humans. However, to date, the cause of sporadic AD (SAD), which is the most frequent form, is still unknown. Although it has not been possible to determine the origin of this disease, the amyloid hypothesis is one of the most accepted to explain the etiology of AD. This hypothesis proposes that the pathogenesis of AD is derived from the toxic effect produced by the amyloid-ß (Aß) peptide in the brain parenchyma, but it does not make clear how Aß is capable of producing such damage. Furthermore, it has been observed that SAD is accompanied by disruptions in the vascular system, such as damage to the blood-brain barrier. This facilitates the transfer of some systemic proteins, such as fibrinogen, to the brain parenchyma, where Aß is abundant. Therefore, this Aß interacts with fibrinogen, which favors the formation of clots resistant to fibrinolysis, inducing a risk of thrombosis and neuroinflammation. Notably, Aß is not only of neuronal origin; platelets also contribute to high Aß production in the circulation. The Aß present in circulation favors the activation of coagulation factor XII, which leads to the generation of thrombin and bradykinin. In addition to Aß-induced platelet activation, all these events favor the development of inflammatory processes that cause damage to the brain vasculature. This damage represents the beginning of the toxic effects of Aß, which supports the amyloid hypothesis. This review addresses the relationship between alterations in the vascular and hemostatic systems caused by Aß and how both alterations contribute to the progression of SAD.
Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Fator XII/metabolismo , Fibrinólise/fisiologia , Ativação Plaquetária/fisiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Amiloide/metabolismo , Animais , Encéfalo/patologia , Humanos , InflamaçãoRESUMO
OBJECTIVE: To verify the efficacy of short-term prophylaxis for vaginal or cesarean section childbirth with plasma-derived C1-inhibitor concentrate in pregnant women. They should have hereditary angioedema (HAE) and normal plasma C1-inhibitor. METHODS: Case report of pregnant women diagnosed with HAE with normal C1-inhibitor who had been treated with intravenous C1-inhibitor concentrate for prophylaxis of angioedema attacks when hospitalized for delivery. The exon 9 of the Factor 12 (F12) genotyping gene was performed by automatic sequencing in all patients. RESULTS: Three cases of pregnant women with HAE with normal serum level of C1-inhibitor are reported. The genetic test detected the presence of a pathogenic mutation in the F12 gene. Deliveries occurred uneventfully and patients had no HAE symptoms in the following 72 hours. CONCLUSION: C1-inhibitor concentrate could be useful to prevent angioedema attacks during and after delivery.
OBJETIVO: Verificar a eficácia da profilaxia de curto prazo para o parto vaginal ou cesáreo com inibidor de C1 derivado de plasma concentrado em mulheres grávidas. Eles devem ter angioedema hereditário e inibidor normal de C1 no plasma. MéTODOS: Relato de caso de gestantes diagnosticadas com angioedema hereditário com inibidor de C1 normal que foram tratadas com inibidor intravenoso de concentrado de C1 para profilaxia de ataques de angioedema quando hospitalizadas para o parto. O exon 9 do gene de genotipagem do fator 12 (F12) foi realizado por sequenciamento automático em todos os pacientes. RESULTADOS: Três casos de gestantes com angioedema hereditário com nível sérico normal de inibidor de C1 são relatados. O teste genético detectou a presença de uma mutação patogênica no gene F12. Os partos ocorreram sem intercorrências e as pacientes não apresentaram sintomas hereditários de angioedema nas 72 horas seguintes. CONCLUSãO: O concentrado de inibidor de C1 pode ser útil para prevenir ataques de angioedema durante e após o parto.
Assuntos
Angioedemas Hereditários/diagnóstico , Fator XII/genética , Complicações na Gravidez/diagnóstico , Diagnóstico Pré-Natal , Adulto , Cesárea , Diagnóstico Diferencial , Feminino , Humanos , Linhagem , Gravidez , Adulto JovemRESUMO
Abstract Objective To verify the efficacy of short-term prophylaxis for vaginal or cesarean section childbirth with plasma-derived C1-inhibitor concentrate in pregnant women. They should have hereditary angioedema (HAE) and normal plasma C1-inhibitor. Methods Case report of pregnant women diagnosed with HAE with normal C1- inhibitor who had been treated with intravenous C1-inhibitor concentrate for prophylaxis of angioedema attacks when hospitalized for delivery. The exon 9 of the Factor 12 (F12) genotyping gene was performed by automatic sequencing in all patients. Results Three cases of pregnant women with HAE with normal serum level of C1- inhibitor are reported. The genetic test detected the presence of a pathogenic mutation in the F12 gene. Deliveries occurred uneventfully and patients had no HAE symptoms in the following 72 hours. Conclusion C1-inhibitor concentrate could be useful to prevent angioedema attacks during and after delivery.
Resumo Objetivo Verificar a eficácia da profilaxia de curto prazo para o parto vaginal ou cesáreo com inibidor de C1 derivado de plasma concentrado em mulheres grávidas. Eles devem ter angioedema hereditário e inibidor normal de C1 no plasma. Métodos Relato de caso de gestantes diagnosticadas com angioedema hereditário com inibidor de C1 normal que foram tratadas com inibidor intravenoso de concentrado de C1 para profilaxia de ataques de angioedema quando hospitalizadas para o parto. O exon 9 do gene de genotipagem do fator 12 (F12) foi realizado por sequenciamento automático em todos os pacientes. Resultados Três casos de gestantes com angioedema hereditário com nível sérico normal de inibidor de C1 são relatados. O teste genético detectou a presença de uma mutação patogênica no gene F12. Os partos ocorreram sem intercorrências e as pacientes não apresentaram sintomas hereditários de angioedema nas 72 horas seguintes. Conclusão O concentrado de inibidor de C1 pode ser útil para prevenir ataques de angioedema durante e após o parto.
Assuntos
Humanos , Feminino , Gravidez , Adulto , Adulto Jovem , Complicações na Gravidez/diagnóstico , Diagnóstico Pré-Natal , Fator XII/genética , Angioedemas Hereditários/diagnóstico , Linhagem , Cesárea , Diagnóstico DiferencialRESUMO
The sensitivity of vertebrate citrated plasma to pro- and anticoagulant venom or toxins occurs on a microscale level (micrograms). Although it improves responses to agonists, recalcification triggers a relatively fast thrombin formation process in mammalian plasma. As it has a natural factor XII deficiency, the recalcification time (RT) of chicken plasma (CP) is comparatively long [≥ 1800 seconds (s)]. Our objective was to compare the ability of bee venom phospholipase A2 (bvPLA2) to neutralize clot formation induced by an activator of coagulation (the aPTT clot) in recalcified human and chicken plasmas, through rotational thromboelastometry. The strategy used in this study was to find doses of bvPLA2 that were sufficient enough to prolong the clotting time (CT) of these activated plasmas to values within their normal RT range. The CT of CP was prolonged in a dose-dependent manner by bvPLA2, with 17 ± 2.8 ng (n = 6) being sufficient to displace the CT values of the activated samples to ≥ 1800 s. Only amounts up to 380 ± 41 ng (n = 6) of bvPLA2 induced the same effect in activated human plasma samples. In conclusion, the high sensitivity of CP to agonists and rotational thromboelastometry could be useful. For example, during screening procedures for assaying the effects of toxins in several stages of the coagulation pathway, such as clot initiation, formation, stability, strength, or dissolution.
Assuntos
Anticoagulantes/toxicidade , Venenos de Abelha/toxicidade , Coagulação Sanguínea/efeitos dos fármacos , Fosfolipases A2/toxicidade , Animais , Galinhas , Fator XII , Feminino , Humanos , Masculino , TromboelastografiaRESUMO
INTRODUCTION AND OBJECTIVES: For long, bleeding in cirrhotic patients has been associated with acquired coagulation disorders. The aim of our study was to investigate the impact of acquired coagulation disorders on bleeding risk in cirrhotic patients. MATERIALS AND METHODS: Blood samples were collected from 51 cirrhotic patients with (H+) or without (H-) bleeding events and 50 controls matched by age and sex. Thrombin generation was assessed as endogenous thrombin potential (ETP). Hemostatic balance was assessed by means of ratios of pro- to anticoagulant factors and by ETP ratio with/without protein C (PC) activator (ETP ratio). RESULTS: Bleeding events occurred in 9 patients (17.6%). Compared with controls, VIII/anticoagulant factors, VII/PC and XII/PC were significantly higher in (H+) patients. No significant difference as regards all ratios across patient groups was detected. ETP ratio was significantly higher in (H+) patients than in controls (p=0.017). However, there was no significant difference between patient groups as regards ETP ratio. CONCLUSION: Hemostatic balance is shifted toward a hypercoagulability state even in cirrhotic patients who experienced bleeding. These findings provide evidence against traditional concept of hemostasis-related bleeding tendency in cirrhotic patients.
Assuntos
Transtornos da Coagulação Sanguínea/sangue , Hemorragia/sangue , Cirrose Hepática/sangue , Trombofilia/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Coagulação Sanguínea , Estudos de Casos e Controles , Fator VII/metabolismo , Fator VIII/metabolismo , Fator XII/metabolismo , Humanos , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Proteína C/metabolismo , Tempo de Protrombina , Risco , Trombina/metabolismo , Adulto JovemRESUMO
The anticoagulant and antithrombotic properties of three structurally correlated sea urchin-derived 3-linked sulfated α-glycans and their low molecular-weight derivatives were screened comparatively through various in vitro and in vivo methods. These methods include activated partial thromboplastin time, the inhibitory activity of antithrombin over thrombin and factor Xa, venous antithrombosis, the inhibition of platelet aggregation, the activation of factor XII, and bleeding. While the 2-sulfated fucan from Strongylocentrotus franciscanus was observed to be poorly active in most assays, the 4-sulfated fucan from Lytechinus variegatus, the 2-sulfated galactan from Echinometra lucunter and their derivatives showed multiple effects. All marine compounds showed no capacity to activate factor XII and similar low bleeding tendencies regardless of the dose concentrations used to achieve the highest antithrombotic effect observed. The 2-sulfated galactan showed the best combination of results. Our work improves the background about the structure-function relationship of the marine sulfated glycans in anticoagulation and antithrombosis. Besides confirming the negative effect of the 2-sulfated fucose and the positive effect of the 2-sulfated galactose on anticoagulation in vitro, our results also demonstrate the importance of this set of structural requirements on antithrombosis in vivo, and further support the involvement of high-molecular weight and 4-sulfated fucose in both activities.