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1.
J Thromb Thrombolysis ; 57(2): 226-234, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37932589

RESUMO

No data is available about pharmacological secondary prevention of superficial vein thrombosis (SVT) despite 10-15% of patients develop venous thromboembolic complications at 3-6 months after an adequate treatment of the acute phase. To verify efficacy and safety of mesoglycan in secondary prevention of SVT recurrence and venous thromboembolic complications. Phase III multicenter, double-blind, randomized, superiority trial comparing mesoglycan 50 mg bid vs placebo in consecutive patients with a SVT extended at least 5 cm, after the initial 45-day treatment course with fondaparinux 2.5 mg once-daily. Primary efficacy outcome: SVT recurrence/extension, symptomatic venous thromboembolism (VTE), asymptomatic proximal deep-vein thrombosis, death. Primary safety outcome: major bleeding. We hypothesized a 12-month 15% incidence of the primary efficacy outcome in placebo group and a 50% risk reduction in mesoglycan group. A bilateral log-rank test with a sample of 650 patients (randomization 1:1) reach a 90% power, with an α-error of 0.025, of detecting a 7.0% difference (HR = 0.51) after 12 months of treatment, considering a 10% patients drop-out. At deadline (December 31, 2022) 570 patients have been randomized (10% drop rate). Mean age was 63.9 years, 58.8% were women. SVT involved great saphenous vein in 69.3%, small saphenous vein in 13.1%, and collaterals in 17.6% of patients. SVT was the first event in 61.7%, a recurrence in 38.3%, provoked in 50.2% and unprovoked in 49.8%. Patients not experiencing a primary outcome, or not retiring their consent will be followed up to December 31, 2024 when the final data analysis will be performedClinicalTrials.gov: NCT03428711.


Assuntos
Glicosaminoglicanos , Tromboembolia Venosa , Trombose Venosa , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Anticoagulantes/uso terapêutico , Método Duplo-Cego , Prevenção Secundária , Resultado do Tratamento , Trombose Venosa/tratamento farmacológico , Trombose Venosa/prevenção & controle , Trombose Venosa/etiologia , Tromboembolia Venosa/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase III como Assunto
2.
J Endocrinol Invest ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971949

RESUMO

PURPOSE: Osteoporotic fragility fractures (FF), particularly those affecting the hip, represent a major clinical and socio-economic concern. These fractures can lead to various adverse outcomes, which may be exacerbated by the presence of sarcopenia, especially among older and frail patients. Early identification of patients with FF is crucial for implementing effective diagnostic and therapeutic strategies to prevent subsequent fractures and their associated consequences. METHODS: The Hip-POS program, implemented at Azienda Ospedale-Università Padova, is a Fracture Liaison Service (FLS) program to evaluate patients aged > 50 years old admitted with fragility hip fractures, involving an interdisciplinary team. After the identification of patients with hip fractures in the Emergency Department, a comprehensive evaluation is conducted to identify risk factors for further fractures, and to assess the main domains of multidimensional geriatric assessment, including muscle status. Patients are then prescribed with anti-fracture therapy, finally undergoing periodic follow-up visits. RESULTS: During the first five months, a total of 250 patients were evaluated (70.4% women, median age 85 years). Following assessment by the Hip-POS team, compared to pre-hospitalization, the proportion of patients not receiving antifracture therapy decreased significantly from 60 to 21%. The prescription rates of vitamin D and calcium increased markedly from 29.6% to 81%. CONCLUSIONS: We introduced the Hip-POS program for the care of older adults with hip fractures. We aspire that our model will represent a promising approach to enhancing post-fracture care by addressing the multifactorial nature of osteoporosis and its consequences, bridging the gap in secondary fracture prevention, and improving patient outcomes.

3.
J Endocrinol Invest ; 43(7): 1009-1018, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31994012

RESUMO

PURPOSE: Although the mortality from acromegaly is due in most cases to an increased cardiovascular risk, no study has globally evaluated the haemostatic balance in acromegaly to ascertain the presence of hypercoagulability. We endeavoured to assess the overall coagulation profile in patients with acromegaly using both traditional and global coagulation assays. METHODS: Consecutive outpatients with a diagnosis of acromegaly were enrolled and matched with healthy subjects. Whole blood thromboelastometry and impedance aggregometry, procoagulant, anticoagulant and fibrinolytic factors, as well as thrombin-generation assay and circulating endothelium-derived microvesicles were measured. RESULTS: Forty patients (M/F 14/26, median age 59 years) with either new diagnosis (naïve, 14 cases) or treated acromegaly (26 cases) were enrolled in this study. Median time from diagnosis was 11 years. Levels of factor VIII and fibrinogen were significantly higher in acromegalic patients vs. controls (p = 0.029 and < 0.003, respectively). Overall, thromboelastometry parameters showed a faster coagulation formation with a more stable clot. Acromegaly patients showed significantly higher endogenous thrombin potential [ETP] and thrombin peak compared to controls (p = 0.016 and p < 0.001, respectively). ETP remained significantly higher (p < 0.001) when thrombomodulin was added. Endothelial-derived microvesicles were significantly higher in acromegaly patients than controls (52 [40.5-67] MVs/µL and 30 [18-80] MVs/µL, p = 0.03). Patients with untreated (naïve) acromegaly showed significantly reduced ETP with and without thrombomodulin vs. patients with treated acromegaly (p = 0.01). CONCLUSION: Hypercoagulability in acromegaly is mainly due to higher levels of fibrinogen, factor VIII and thrombin generation, and appears to be more linked to the chronic phase of the disease.


Assuntos
Acromegalia/sangue , Hemostasia/fisiologia , Idoso , Coagulação Sanguínea/fisiologia , Testes de Coagulação Sanguínea , Estudos de Casos e Controles , Fator VIII/metabolismo , Feminino , Fibrinogênio/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Trombina/metabolismo , Trombomodulina/sangue
4.
Haemophilia ; 24(4): 648-656, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29578313

RESUMO

INTRODUCTION: Severe congenital factor V (FV) deficiency is a rare bleeding disorder characterized by very low/undetectable levels of FV. Fresh frozen plasma is the standard treatment for bleeding manifestations. Recently, a novel plasma-derived FV concentrate has been developed. AIM: To evaluate the "in vitro" ability of the novel FV concentrate to normalize clotting times and generate normal amount of thrombin in plasma collected from patients with severe FV deficiency. METHODS: Prothrombin time (PT), activated partial thromboplastin time (aPTT), FV activity and antigen levels and thrombin generation were measured pre- and postspiking of plasma samples of 10 patients with increasing doses of FV concentrate (from 0 to 100 IU/dL). RESULTS: Prothrombin time and activated partial thromboplastin time ratios as well as all thrombin generation parameters were fully corrected by the addition of FV concentrate at a final concentration of 25 IU/dL. However, the addition of FV at a concentration of 1-3 IU/dL was already sufficient to correct peak height and endogenous thrombin potential (but not lag time and time to peak) after activation with 5 pmol/L tissue factor. FV activity and antigen levels showed a linear response to supplementation with the novel FV concentrate. CONCLUSION: The novel plasma-derived FV concentrate was effective to correct "in vitro" severe FV deficiency in patients. The optimal FV concentration to fully normalize both global clotting times and thrombin generation parameters using the novel plasma-derived FV concentrate was 25 IU/dL.


Assuntos
Deficiência do Fator V/tratamento farmacológico , Fator V/uso terapêutico , Plasma/metabolismo , Adulto , Idoso , Testes de Coagulação Sanguínea , Fator V/farmacologia , Deficiência do Fator V/metabolismo , Deficiência do Fator V/fisiopatologia , Feminino , Hemostasia/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Trombina/biossíntese
5.
Am J Transplant ; 16(7): 2016-29, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26749114

RESUMO

Neural transplantation is a promising therapeutic approach for neurodegenerative diseases; however, many patients receiving intracerebral fetal allografts exhibit signs of immunization to donor antigens that could compromise the graft. In this context, we intracerebrally transplanted mesencephalic pig xenografts into primates to identify a suitable strategy to enable long-term cell survival, maturation, and differentiation. Parkinsonian primates received WT or CTLA4-Ig transgenic porcine xenografts and different durations of peripheral immunosuppression to test whether systemic plus graft-mediated local immunosuppression might avoid rejection. A striking recovery of spontaneous locomotion was observed in primates receiving systemic plus local immunosuppression for 6 mo. Recovery was associated with restoration of dopaminergic activity detected both by positron emission tomography imaging and histological examination. Local infiltration by T cells and CD80/86+ microglial cells expressing indoleamine 2,3-dioxigenase were observed only in CTLA4-Ig recipients. Results suggest that in this primate neurotransplantation model, peripheral immunosuppression is indispensable to achieve the long-term survival of porcine neuronal xenografts that is required to study the beneficial immunomodulatory effect of local blockade of T cell costimulation.


Assuntos
Antígeno CTLA-4/imunologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Terapia de Imunossupressão/métodos , Neurônios/citologia , Doença de Parkinson/terapia , Linfócitos T/imunologia , Animais , Animais Geneticamente Modificados , Células Cultivadas , Feminino , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Xenoenxertos , Imunossupressores/uso terapêutico , Ativação Linfocitária , Macaca fascicularis , Masculino , Neurônios/imunologia , Doença de Parkinson/imunologia , Sus scrofa , Transplante Heterólogo
6.
Am J Transplant ; 15(2): 358-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25612490

RESUMO

Galactosyl-transferase KO (GalT-KO) pigs represent a potential solution to xenograft rejection, particularly in the context of additional genetic modifications. We have performed life supporting kidney xenotransplantation into baboons utilizing GalT-KO pigs transgenic for human CD55/CD59/CD39/HT. Baboons received tacrolimus, mycophenolate mofetil, corticosteroids and recombinant human C1 inhibitor combined with cyclophosphamide or bortezomib with or without 2-3 plasma exchanges. One baboon received a control GalT-KO xenograft with the latter immunosuppression. All immunosuppressed baboons rejected the xenografts between days 9 and 15 with signs of acute humoral rejection, in contrast to untreated controls (n = 2) that lost their grafts on days 3 and 4. Immunofluorescence analyses showed deposition of IgM, C3, C5b-9 in rejected grafts, without C4d staining, indicating classical complement pathway blockade but alternate pathway activation. Moreover, rejected organs exhibited predominantly monocyte/macrophage infiltration with minimal lymphocyte representation. None of the recipients showed any signs of porcine endogenous retrovirus transmission but some showed evidence of porcine cytomegalovirus (PCMV) replication within the xenografts. Our work indicates that the addition of bortezomib and plasma exchange to the immunosuppressive regimen did not significantly prolong the survival of multi-transgenic GalT-KO renal xenografts. Non-Gal antibodies, the alternative complement pathway, innate mechanisms with monocyte activation and PCMV replication may have contributed to rejection.


Assuntos
Ácidos Borônicos/uso terapêutico , Proteína Inibidora do Complemento C1/uso terapêutico , Galactosiltransferases/genética , Sobrevivência de Enxerto/fisiologia , Xenoenxertos , Transplante de Rim , Troca Plasmática , Pirazinas/uso terapêutico , Animais , Animais Geneticamente Modificados , Doenças Autoimunes , Bortezomib , Citomegalovirus/fisiologia , Galactosiltransferases/deficiência , Técnicas de Inativação de Genes , Imunidade Inata/fisiologia , Imunossupressores/uso terapêutico , Rim/cirurgia , Rim/virologia , Modelos Animais , Papio anubis , Sus scrofa , Replicação Viral/fisiologia
7.
Haemophilia ; 21(2): 241-248, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25470420

RESUMO

Coagulation factor V (FV) deficiency is a rare autosomal recessive bleeding disorder. We investigated a patient with severe FV deficiency (FV:C < 3%) and moderate bleeding symptoms. Thrombin generation experiments showed residual FV expression in the patient's plasma, which was quantified as 0.7 ± 0.3% by a sensitive prothrombinase-based assay. F5 gene sequencing identified a novel missense mutation in exon 4 (c.578G>C, p.Cys193Ser), predicting the abolition of a conserved disulphide bridge, and an apparently synonymous variant in exon 8 (c.1281C>G). The observation that half of the patient's F5 mRNA lacked the last 18 nucleotides of exon 8 prompted us to re-evaluate the c.1281C>G variant for its possible effects on splicing. Bioinformatics sequence analysis predicted that this transversion would activate a cryptic donor splice site and abolish an exonic splicing enhancer. Characterization in a F5 minigene model confirmed that the c.1281C>G variant was responsible for the patient's splicing defect, which could be partially corrected by a mutation-specific morpholino antisense oligonucleotide. The aberrantly spliced F5 mRNA, whose stability was similar to that of the normal mRNA, encoded a putative FV mutant lacking amino acids 427-432. Expression in COS-1 cells indicated that the mutant protein is poorly secreted and not functional. In conclusion, the c.1281C>G mutation, which was predicted to be translationally silent and hence neutral, causes FV deficiency by impairing pre-mRNA splicing. This finding underscores the importance of cDNA analysis for the correct assessment of exonic mutations.


Assuntos
Processamento Alternativo , Deficiência do Fator V/genética , Fator V/genética , Mutação , Animais , Linhagem Celular , Éxons , Deficiência do Fator V/sangue , Deficiência do Fator V/diagnóstico , Expressão Gênica , Humanos , Masculino , Trombina/biossíntese , Adulto Jovem
8.
Pituitary ; 17(1): 68-75, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23408210

RESUMO

Cushing's Syndrome (CS) is associated with an increased mortality, where hypercoagulability seems to have a crucial role in both arterial and venous thrombosis. Parameters of in vitro thrombin generation (TG) such as lag time, peak thrombin and endogenous thrombin potential (ETP), that describe the time until thrombin burst, the peak amount of TG and the total amount of thrombin generated, respectively as well as classical clotting markers were evaluated in 33 CS patients compared to both a group of 28 patients matched for the features of Metabolic Syndrome (MetS) and 31 healthy individuals. CS and MetS patients had shorter lag time (p < 0.0001), higher peak and ETP (p < 0.0001) than healthy controls, though lag time was less shortened in CS (p < 0.0001) respect to MetS group. Prothrombin time (PT) was increased (p < 0.0001) in both CS and MetS patients, while partial thromboplastin time (PTT) was shorter (p < 0.0001) in CS compared to both MetS and healthy group (p < 0.0001). Factor VIII (FVIII), Antithrombin (AT), protein C and S were increased only in CS patients (p < 0.0001). lag time, AT and FVIII correlated to night salivary cortisol (r = + 0.59; p = 0.0005, r = + 0.40; p = 0.003, r = + 0.40; p = 0.04, respectively); PTT correlated inversely to urinary free cortisol (r = -0.45; p = 0.009). BMI correlated negatively to lag time (r = -0.40; p = 0.0001) and positively to peak and ETP (r = + 0.34; p = 0.001, r = + 0.28; p = 0.008, respectively). Obese and diabetic patients had shorter lag time (p = 0.0005; p = 0.0002, respectively), higher ETP (p = 0.0006; p = 0.007, respectively) and peak (p = 0.0003; p = 0.0005, respectively) as well as a more prolonged PT (p = 0.04; p = 0.009, respectively). Hypertensive individuals had higher ETP (p = 0.004), peak (p = 0.0008) and FVIII (p = 0.001). Our findings confirm a prothrombotic state in both CS and MetS patients, though lag time was less shortened in CS. The high levels of endogenous physiological anticoagulants, could possibly represent a protective mechanism against hypercoagulability seen in CS patients.


Assuntos
Testes de Coagulação Sanguínea , Coagulação Sanguínea/fisiologia , Síndrome de Cushing/sangue , Síndrome Metabólica/sangue , Trombina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome de Cushing/complicações , Complicações do Diabetes/sangue , Dislipidemias/complicações , Feminino , Humanos , Hidrocortisona/metabolismo , Hipertensão/complicações , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Obesidade/complicações
9.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 166763, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37951510

RESUMO

Metabolic dysfunction-associated fatty liver disease (MAFLD), the hepatic component of the metabolic syndrome caused by insulin resistance, is a major public health problem, affecting about the 25 % of the general population in Western countries. Morbidity and mortality of MAFLD patients is increased primarily due to cardiovascular disease (CVD). Liver fibrosis, the byproduct of hepatic repair, is the main determinant of MAFLD progression and the strongest predictor for overall mortality. Since the mechanistic relationship between MAFLD, fibrosis, insulin resistance and the cardiometabolic risk is far to be clear, deciphering the functional link of hepatic fibrogenesis with genetic factors and hypercoagulability in MAFLD-associated CVD may hold translational potential for risk profiling and innovative therapeutic targeting.


Assuntos
Doenças Cardiovasculares , Resistência à Insulina , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Humanos , Doenças Cardiovasculares/etiologia , Cirrose Hepática/complicações , Hepatopatia Gordurosa não Alcoólica/complicações , Síndrome Metabólica/complicações
11.
Haemophilia ; 18(3): 463-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22176523

RESUMO

Severe factor V (FV) deficiency (parahaemophilia) is a rare congenital hemorrhagic disorder characterized by very low or undetectable plasma FV levels and bleeding phenotype ranging from mild to severe. We evaluated whole blood (WB) rotation thromboelastometry (ROTEM) in parahaemophilia patients and the contribution of intraplatelets FV, if any, to clot formation. Standard ROTEM(®) assays were performed in WB from nine parahaemophilia patients and 50 healthy controls. In addition, platelets poor plasma from one parahaemophilia patient (PPP-Pt) or normal subjects (PPP-N) was reconstituted with washed platelets obtained either from one patient with parahaemophilia (Plts-Pt) or normal subjects (Plts-N) and ROTEM assays were performed in platelets rich plasma (PRP) samples. There was a prolongation of the WB clotting time (CT) in all assays in patients as compared with controls. However, maximum clot firmness (MCF) was similar in patients and controls. ROTEM in PPP-Pt showed both a prolongation of CT and a reduction of MCF as compared with PPP-N. The addition of either Plts-Pt or Plts-N to PPP-Pt resulted in similar increase in MCF and a decrease of CT which was more evident for PPP-Pt + Plts-N than PPP-Pt + Plts-Pt. In contrast, the addition of Plts-Pt or Plts-N to PPP-N had superimposable effects on both CT and MCF. In parahaemophilia patients, WB ROTEM(®) presents mainly with prolongation of CT and no relevant effect on MCF. Residual intraplatelets FV in parahaemophilia contributes significantly to thrombin generation as shown in artificially reconstituted PRP models.


Assuntos
Fatores de Coagulação Sanguínea/fisiologia , Coagulação Sanguínea/fisiologia , Deficiência do Fator V/sangue , Tromboelastografia/métodos , Adulto , Área Sob a Curva , Deficiência do Fator V/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Plant Biol (Stuttg) ; 23(6): 1128-1140, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34486807

RESUMO

This study represents an important contribution to the structural, histochemical and biological understanding of ducts and cavities in leaves of four species of Calophyllaceae that occur in Amazonian savannas. Samples of adult leaves were processed using light, scanning and transmission electron microscopy, as per usual methods for plant anatomy. In paradermal sections, the lumina of ducts are elongated while those of cavities are short. Ducts occur exclusively in the central rib and are abundant in Kielmeyera rubriflora Cambess and Kielmeyera coriacea Mart. and Zucc and larger than in Calophyllum brasiliense Cambess and Caraipa densifolia Mart. In mesophyll, the type of secretory structure and distribution pattern of the ducts and cavities are distinct. In most species, the secreted metabolites are similar and consist of phenolic compounds, lipids, essential oils with oleoresins, mucilage, neutral polysaccharides, proteins and alkaloids, except in K. coriacea, which does not contain oleoresin. The secretion is probably synthesized by mitochondria, rough endoplasmic reticulum, ribosomes and dictyosomes and is externalized toward the lumen by granulocrine and eccrine processes. In addition to being of diagnostic value for species identification, the attributes of the lumen shape, type of secretory structure, distribution pattern, identified metabolites and secretion mechanism are important for understanding the biological roles of ducts and cavities. The identified metabolites reveal a capacity for adaptation, resistance and protection from the action of herbivores and pathogens, and in water retention.


Assuntos
Pradaria , Óleos Voláteis , Microscopia Eletrônica de Transmissão , Folhas de Planta
13.
Vascul Pharmacol ; 130: 106682, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32438078

RESUMO

No data are available on rivaroxaban use in renal transplant recipients and on its surmised interaction with immunosuppressants. The aim was to investigate potential interactions between rivaroxaban and immunosuppressants in this setting. Renal transplant recipients with a stable renal function treated with rivaroxaban and tacrolimus with or without everolimus were investigated. All drugs and creatinine concentrations were determined daily for 2 weeks after the start of anticoagulation. Blood samples were drawn at 8.00 am and 3-4 h later for trough and peak concentrations, respectively. Bleeding and thrombotic events were recorded during a minimum follow-up of 6 months. In 8 renal transplant patients, rivaroxaban levels showed a predictable pharmacokinetic trend, both at Ctrough (30-61 µg/L) and at Cpeak (143-449 µg/L), with limited variability in the 25th-75th percentile range. Tacrolimus (Ctrough 3-13 µg/L; Cpeak 3-16 µg/L), everolimus (Ctrough 3-11 µg/L; Cpeak 5-17 µg/L) and creatinine concentrations were stable as well. Immunosuppressors variability before and after rivaroxaban were 30% and 30% for tacrolimus, 27% and 29% for everolimus, respectively, as well as 14% and 3% for creatinine. For rivaroxaban monitoring, the reference change value better performed in identifying significant variations of its concentration. No patient had bleeding or thrombotic events, worsening of renal graft function, and signs of immunosuppressants toxicity during a mean follow-up of 23 (9-28) months. In conclusion, rivaroxaban does not seem to interact with tacrolimus and everolimus in renal transplant recipients. Both anticoagulant and immunosuppressive effects seem warranted, without major bleeding complications and effect on the graft function.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Everolimo/farmacocinética , Inibidores do Fator Xa/farmacocinética , Imunossupressores/farmacocinética , Transplante de Rim , Rivaroxabana/farmacocinética , Tacrolimo/farmacocinética , Trombose Venosa/tratamento farmacológico , Idoso , Fibrilação Atrial/sangue , Fibrilação Atrial/diagnóstico , Coagulação Sanguínea/efeitos dos fármacos , Interações Medicamentosas , Monitoramento de Medicamentos , Everolimo/efeitos adversos , Everolimo/sangue , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/sangue , Feminino , Sobrevivência de Enxerto/efeitos dos fármacos , Hemorragia/induzido quimicamente , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/sangue , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Rivaroxabana/efeitos adversos , Rivaroxabana/sangue , Tacrolimo/efeitos adversos , Tacrolimo/sangue , Resultado do Tratamento , Trombose Venosa/sangue , Trombose Venosa/diagnóstico
15.
Thromb Haemost ; 118(2): 251-265, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29378353

RESUMO

Cancer induces a systemic hypercoagulable state that elevates the baseline thrombotic risk of affected patients. This hypercoagulable state reflects a complex interplay between cancer cells and host cells and the coagulation system as part of the host response to cancer. Although the tissue factor (TF)/factor VIIa pathway is proposed to be the principal initiator of fibrin formation in cancer patients, clinical studies have not shown a consistent relationship between circulating TF levels (often measured as plasma microvesicle-associated TF) and the risk of thrombosis. A renewed interest in the role of the contact pathway in thrombosis has evolved over the past decade, raising the question of its role in the pathogenesis of thrombotic complications in cancer. Recent observations have documented the presence of activation of the contact system in gastrointestinal, lung, breast and prostate cancers. Although the assays used to measure contact activation differ, and despite the absence of standardization of methodologies, it is clear that both the intrinsic and extrinsic pathways may be activated in cancer. This review will focus on recent findings concerning the role of activation of the contact system in cancer-associated hypercoagulability and thrombosis. An improved understanding of the pathophysiology of these mechanisms may lead to personalized antithrombotic protocols with improved efficacy and safety compared with currently available therapies.


Assuntos
Neoplasias/complicações , Neoplasias/metabolismo , Trombose/complicações , Trombose/metabolismo , Animais , Coagulação Sanguínea , Micropartículas Derivadas de Células/metabolismo , DNA/análise , Fator XII/metabolismo , Fibrina/química , Glicosaminoglicanos/metabolismo , Humanos , Neoplasias/fisiopatologia , Neutrófilos/metabolismo , Tempo de Tromboplastina Parcial , Ativação Plaquetária , Tromboplastina/metabolismo , Trombose/fisiopatologia
16.
J Thromb Haemost ; 5(5): 971-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17461930

RESUMO

BACKGROUND: Hyperprothrombinemia, resulting from the prothrombin G20210A mutation or other causes, is associated with activated protein C (APC) resistance and increased thrombosis risk. When high prothrombin levels are a result of increased hepatic biosynthesis, these effects may be counteracted by concomitantly increased levels of the anticoagulant factors (particularly protein S). Differently, in prothrombin G20210A carriers only prothrombin levels are elevated. OBJECTIVE: To investigate whether prothrombin G20210A carriers have a more severe hypercoagulable state than non-carriers with comparable prothrombin levels. PATIENTS/METHODS: Coagulation factor levels, thrombin generation (Calibrated Automated Thrombogram in the presence and absence of APC) and APC resistance were measured in normal (n = 132), heterozygous (n = 167) and homozygous (n = 3) individuals. RESULTS: Prothrombin levels, thrombin generation and APC resistance were higher in carriers of the prothrombin G20210A mutation (especially those who had experienced venous thrombosis) than in non-carriers, whereas protein S and antithrombin levels were similar among genotype groups. Because individuals with high prothrombin levels in the absence of the prothrombin G20210A mutation tend to have all liver-synthesized factors elevated, carriers of the mutation had lower protein S and antithrombin levels than non-carriers with equally high prothrombin levels. Accordingly, they also generated more thrombin and showed a tendency toward higher APC resistance. Analogous effects, but less pronounced, were observed in homozygotes for the prothrombin A19911G polymorphism, which also upregulates prothrombin levels. CONCLUSIONS: Individuals with hyperprothrombinemia as a result of prothrombin gene mutations generate more thrombin and tend to be more APC-resistant than individuals with comparable prothrombin levels because of other causes.


Assuntos
Protrombina/metabolismo , Trombina/biossíntese , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Criança , Pré-Escolar , Primers do DNA , Feminino , Triagem de Portadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Protrombina/genética
17.
J Thromb Haemost ; 5(11): 2193-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17958738

RESUMO

BACKGROUND: The relationship between the G20210A prothrombin variant (PT-G20210A) and adverse pregnancy outcome has been studied by several groups in the last few years. However, because of the different design and sample sizes of these studies the estimated risks have varied. OBJECTIVE: In this retrospective, multi-center, cohort study we assessed the risk of thromboembolic or obstetric complications in women belonging to families of probands with isolated PT-G20210A and that were symptomatic for venous thromboembolism (VTE). METHODS: Two hundred and eighty-three female family members that had been pregnant at least once were enrolled. The occurrence of VTE and obstetric complications during pregnancy and postpartum were assessed in carriers of PT-G20210A and compared with non- carriers. RESULTS: One thromboembolic event occurred during the postpartum period in the carriers group. In the same group, 48 out of 359 pregnancies resulted in unexplained fetal loss as compared with 50 out of 357 pregnancies in the non-carriers (RR 0.9; 95% CI: 0.7-1.4). After adjustment, carriers of PT-G20210A showed a trend towards a higher risk of late fetal loss as compared with non-carriers (RR 2.2; 95% CI: 0.8-6.2). Furthermore, in pregnancies subsequent to those with previous fetal loss there was not a different risk of adverse outcome regardless of the carrier status. CONCLUSIONS: Female family members who are heterozygous carriers of isolated PT-G20210A do not seem to be at significant increased risk for fetal loss as compared with non-carriers. Screening for PT-G20210A of fertile age women belonging to these families is not warranted in this situation.


Assuntos
Morte Fetal/genética , Polimorfismo de Nucleotídeo Único , Complicações Hematológicas na Gravidez/genética , Protrombina/genética , Trombose Venosa/genética , Adulto , Estudos de Coortes , Saúde da Família , Feminino , Morte Fetal/epidemiologia , Morte Fetal/etiologia , Genótipo , Humanos , Gravidez , Complicações Hematológicas na Gravidez/epidemiologia , Complicações Hematológicas na Gravidez/etiologia , Embolia Pulmonar/etiologia , Embolia Pulmonar/genética , Estudos Retrospectivos , Fatores de Risco , Trombose Venosa/etiologia
19.
Braz J Med Biol Res ; 40(8): 1111-20, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17665048

RESUMO

Aging is accompanied by a decrease in several physiological functions that make older individuals less responsive to environmental challenges. In the present study, we analyzed the immune response of female BALB/c mice (N = 6) of different ages (from 2 to 96 weeks) and identified significant age-related alterations. Immunization with hapten-protein (trinitrophenyl-bovine serum albumin) conjugates resulted in lower antibody levels in the primary and secondary responses of old mice (72 weeks old). Moreover, young mice (2, 16, and 32 weeks old) maintained specific antibodies in their sera for longer periods after primary immunization than did old mice. However, a secondary challenge efficiently induced memory in old mice, as shown by the increased antibody levels in their sera. The number of CD4+ and CD8+ T cells in the spleen increased until 8 weeks of age but there was no change in the CD4+/CD8+ ratio with aging. Splenic T cells from old mice that had or had not been immunized were less responsive to concanavalin-A and showed reduced cytokine production compared to young mice (IL-2: 57-127 vs 367-1104 pg/mL, IFN-gamma: 2344-12,836 vs 752-23,106 pg/mL and IL-10: 393-2172 vs 105-2869 pg/mL in old and young mice, respectively). These data suggest that there are significant changes in the organization of the immune system throughout life. However, the relevance of these alterations for the functioning of the immune system is unknown.


Assuntos
Envelhecimento/imunologia , Citocinas/biossíntese , Haptenos/imunologia , Baço/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Relação CD4-CD8 , Proliferação de Células/efeitos dos fármacos , Concanavalina A/farmacologia , Feminino , Imunidade Celular/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Mitógenos/farmacologia , Baço/citologia
20.
J Vet Intern Med ; 31(1): 43-50, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27862300

RESUMO

BACKGROUND: Ascitic fluids of horses and humans have fibrinolytic activity, independent of the underlying mechanism of fluid formation. OBJECTIVE: To determine whether coagulation and fibrinogenolytic/fibrinolytic activity (ie, low fibrinogen and increased fibrin-fibrinogen degradation products [FDPs], D-dimer, or both) occur in all types of ascitic fluid in dogs. ANIMALS: A total of 70 client-owned dogs with ascites. METHODS: In this cross-sectional study, dogs were categorized based on the pathophysiology of fluid formation into 4 groups: transudates due to decreased osmotic pressure, transudates due to increased hydrostatic pressure, exudates, and hemorrhagic ascites. Fibrinogen, FDPs, and D-dimer concentrations were measured and then compared in both ascitic fluid and plasma. RESULTS: Ten dogs had transudates due to decreased colloid osmotic pressure, 18 had transudates due to increased hydrostatic pressure, 13 had exudates, and 29 had hemorrhagic ascites. Ascitic fibrinogen concentrations (n = 70) were significantly lower (median = 59 mg/dL; range: 59-122 mg/dL) than those in the plasma (median = 168 mg/dL, range: 59-879 mg/dL; P < .0001). Ascitic FDPs concentrations (n = 70) were significantly higher (<5 µg/mL: 3/70 dogs, ≥5 to <20 µg/mL: 11/70 dogs, ≥20 µg/mL: 56/70 dogs) than those in the plasma (<5 µg/mL: 17/70 dogs, ≥5 to <20 µg/mL: 28/70 dogs, ≥20 µg/mL: 25/70 dogs; P < .0001). Ascitic D-dimer concentrations (n = 70) were significantly higher (median = 3.98 µg/mL, range: 0.02-9.19) than those in the plasma (median = 0.11 µg/mL, range: 0.01-4.08; P < .0001). Analysis of the data for each of the 4 different types of ascites showed similar results to those of all the data analyzed together. CONCLUSIONS AND CLINICAL IMPORTANCE: Ascitic fluid of dogs has evidence of coagulation activation and fibrinogenolytic/fibrinolytic activity and that this phenomenon occurs independent of the underlying mechanism that leads to the formation of ascites.


Assuntos
Ascite/veterinária , Líquido Ascítico/metabolismo , Transtornos da Coagulação Sanguínea/veterinária , Doenças do Cão/metabolismo , Animais , Ascite/metabolismo , Transtornos da Coagulação Sanguínea/metabolismo , Estudos Transversais , Cães , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinogênio/metabolismo , Masculino , Tempo de Tromboplastina Parcial
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