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1.
Haemophilia ; 24(5): 733-740, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29963724

RESUMO

INTRODUCTION: Recombinant factor VIII (rFVIII) products with extended half-lives, such as BAY 94-9027, can potentially maintain higher FVIII levels for longer periods of time, thus providing improved bleeding protection vs standard-acting FVIII products. AIM: To characterize the pharmacokinetic (PK) profile of BAY 94-9027 from phase 1, phase 2/3 (PROTECT VIII) and phase 3 (PROTECT VIII Kids) clinical trials in adults, adolescents and children with severe haemophilia A METHODS: Patients with severe haemophilia A (FVIII <1%) with >50 FVIII exposure days (EDs) and no history of inhibitors were included in the phase 1 (18-65 years, ≥150 EDs), PROTECT VIII (12-65 years, ≥150 EDs) and PROTECT VIII Kids (<12 years, >50 EDs) trials. PK parameters were assessed following a 25-IU/kg or 60-IU/kg BAY 94-9027 dose in the phase 1 study after the first and repeated infusion, in PROTECT VIII after the first and repeated 60-IU/kg infusion and in PROTECT VIII Kids after a single 60-IU/kg infusion. The chromogenic assay was used to assess FVIII activity. RESULTS: Compared with sucrose-formulated rFVIII, BAY 94-9027 had reduced clearance that resulted in a ~1.4-fold increase in half-life and dose-normalized area under the curve (AUC). The BAY 94-9027 PK profile was comparable after single- and repeated-dose administrations. Dose-proportional increases were observed between 25- and 60-IU/kg administrations. BAY 94-9027 PK characteristics were age dependent, consistent with other FVIII products. CONCLUSIONS: BAY 94-9027 shows an extended half-life and increased AUC vs standard-acting FVIII products. These PK characteristics will result in higher FVIII levels for longer duration.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Polietilenoglicóis/uso terapêutico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Fator VIII/farmacocinética , Fator VIII/farmacologia , Hemofilia A/patologia , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia , Adulto Jovem
2.
Haemophilia ; 22(5): 706-12, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27339736

RESUMO

INTRODUCTION: BAY 81-8973 (Kovaltry(®) ) is a full-length, unmodified recombinant human factor VIII (FVIII) with the same amino acid sequence as sucrose-formulated recombinant FVIII and is produced using additional advanced manufacturing technologies. AIM: To demonstrate efficacy and safety of BAY 81-8973 for treatment of bleeds and as prophylaxis based on two different potency assignments. METHODS: In LEOPOLD I (ClinicalTrials.gov identifier, NCT01029340), males aged 12-65 years with severe haemophilia A and ≥150 exposure days received BAY 81-8973 20-50 IU kg(-1) two or three times per week for 12 months. Potency was based on chromogenic substrate assay per European Pharmacopoeia and label adjusted to mimic one-stage assay potency. Patients were randomized for potency sequence and crossed over potency groups after 6 months, followed by an optional 12-month extension. Primary efficacy endpoint was annualized bleeding rate (ABR). Patients also received BAY 81-8973 during major surgeries. RESULTS: Sixty-two patients received BAY 81-8973 prophylaxis and were included in the analysis. Median ABR was 1.0 (quartile 1, 0; quartile 3, 5.1) without clinically relevant differences between potency periods. Median ABR was similar for twice-weekly vs. three times-weekly dosing (1.0 vs. 2.0). Haemostasis was maintained during 12 major surgeries. Treatment-related adverse event (AE) incidence was ≤7% overall; no patient developed inhibitors. One patient with risk factors for cardiovascular disease developed a myocardial infarction. CONCLUSIONS: BAY 81-8973 was efficacious in preventing and treating bleeding episodes, irrespective of the potency assignment method, with few treatment-related AEs. Caution should be used when treating older patients with cardiovascular risk factors.


Assuntos
Coagulantes/uso terapêutico , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Coagulantes/efeitos adversos , Coagulantes/farmacocinética , Estudos Cross-Over , Relação Dose-Resposta a Droga , Esquema de Medicação , Fator VIII/efeitos adversos , Fator VIII/farmacocinética , Meia-Vida , Hemofilia A/patologia , Hemorragia/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Ortopedia , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
3.
Haemophilia ; 22(3): 349-53, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26931631

RESUMO

INTRODUCTION: BAY 81-8973 is a recombinant factor VIII (rFVIII) with the same amino acid sequence as Bayer's sucrose-formulated rFVIII (rFVIII-FS) but manufactured with certain more advanced technologies. AIM: To describe surgery outcomes with BAY 81-8973 in the LEOPOLD trials. METHODS: Male patients with severe haemophilia A and no inhibitors aged 12-65 years with ≥150 exposure days (EDs) to FVIII (LEOPOLD I and II), or aged ≤12 years with ≥50 EDs to FVIII (LEOPOLD Kids), received BAY 81-8973 based on dosing recommendations for rFVIII-FS according to surgical requirements. Haemostasis-related complications, investigator/surgeon assessment of haemostasis, blood loss, need for transfusion and use of BAY 81-8973 were determined. RESULTS: In LEOPOLD I and II, 11 patients (mean age, 35.3 years) underwent 13 major surgeries. In LEOPOLD Kids, one patient (aged 6 years) underwent one major surgery. Thirty-two adult and paediatric patients underwent 46 minor surgeries. Haemostasis was rated good or excellent in all major and minor surgeries. Blood loss during surgery did not exceed expected amounts; blood transfusions were required in three of the 14 major surgeries. For major surgeries in LEOPOLD I and II, patients received a presurgical 50-IU kg(-1) dose of BAY 81-8973; median nominal dose on day of surgery was 7000 IU (107.5 IU kg(-1) ). Total BAY 81-8973 dose was 2500 IU (108.7 IU kg(-1) ) on the day of the only major surgery in LEOPOLD Kids. No haemostasis-related complications were reported. CONCLUSIONS: Haemostatic control with BAY 81-8973 during all surgeries in the LEOPOLD trials was good or excellent, with no haemostasis-related complications.


Assuntos
Coagulantes/uso terapêutico , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Adolescente , Adulto , Idoso , Transfusão de Sangue , Criança , Coagulantes/efeitos adversos , Coagulantes/farmacocinética , Estudos Cross-Over , Fator VIII/efeitos adversos , Fator VIII/farmacocinética , Hemofilia A/patologia , Hemorragia/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Operatórios , Resultado do Tratamento , Adulto Jovem
4.
Neth Heart J ; 23(7-8): 392-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26043925

RESUMO

This case report discusses a 23-year-old male patient who presented with shortness of breath during exercise. Echocardiography revealed an intracardiac mass located on the mitral valve. His medical history included surgical closure of an atrial septal defect type 2 at the age of 2 years. After being discussed within a multidisciplinary heart team, the intracardiac mass was surgically removed. Histopathological examination revealed a blood cyst. This case report emphasises that the presence of an acquired intracardiac cyst is a rare entity and that a pathophysiological association between the formation of a blood cyst and previous cardiac surgery has not been proven yet.

5.
Haemophilia ; 21(6): 766-71, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25952661

RESUMO

INTRODUCTION: BAY 81-8973 is a full-length recombinant factor VIII (FVIII) with the same primary amino acid sequence as sucrose-formulated recombinant FVIII (rFVIII-FS) but is produced with advanced manufacturing technologies. AIM: To analyse the pharmacokinetics (PK) of BAY 81-8973 after single and multiple dosing across different age and ethnic groups in the LEOPOLD clinical trial programme. METHODS: The LEOPOLD trials enrolled patients with severe haemophilia A aged 12-65 years (LEOPOLD I and II) or ≤12 years (LEOPOLD Kids) with ≥150 (LEOPOLD I and II) or ≥50 (LEOPOLD Kids) exposure days to any FVIII product and no history of FVIII inhibitors. PK were assessed using chromogenic and one-stage assays (only chromogenic assay for LEOPOLD Kids) after a single 50-IU kg(-1) dose of BAY 81-8973 and, in a subset of patients in LEOPOLD I, after repeated dosing. Pharmacokinetic analyses were also performed based on age (18 to 65, 12 to <18, 6 to <12 and <6 years) and ethnicity (Asian and non-Asian). RESULTS: Pharmacokinetic assessments in the LEOPOLD I trial showed non-inferiority of BAY 81-8973 vs. rFVIII-FS. The PK of BAY 81-8973 were comparable after single and multiple dosing. Age-based analysis in the three trials showed that plasma concentrations were slightly lower for children, but similar for adolescents compared with adults. Pharmacokinetic results were similar in the different ethnic groups. CONCLUSIONS: Results of the LEOPOLD trials show that the BAY 81-8973 pharmacokinetic profile is non-inferior to rFVIII-FS. Similar BAY 81-8973 pharmacokinetic values were observed following single and repeated dosing and across ethnic groups.


Assuntos
Fator VIII/farmacocinética , Proteínas Recombinantes/farmacocinética , Adolescente , Adulto , Envelhecimento/metabolismo , Criança , Pré-Escolar , Etnicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Haemophilia ; 20(3): 354-61, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24847524

RESUMO

Prospective data on the efficacy of secondary prophylaxis in adults with haemophilia A are limited. To analyse bleeding outcomes in the sucrose-formulated recombinant factor VIII [rFVIII-FS (control)] arm of the LIPLONG study, a randomized, double-blind, 52-week trial was conducted in patients with severe haemophilia A receiving prophylaxis with the investigational product BAY 79-4980 or rFVIII-FS. The per-protocol population of previously treated patients with severe haemophilia A without a history of inhibitors (n = 68 males; mean age, 34.4 years) received 25 IU kg−1 rFVIII-FS three times per week for a median of 50.7 weeks. Annualized bleeding rates were assessed and analysed according to predefined target joint status at study start, prestudy treatment type (prophylaxis vs. on demand), age (<30 or ≥30 years), geographical region, bleeding frequency during the previous 6 months and physical activity status during the study using the Student t-test. The annualized median (range) number of bleeds was 2.2 (0.0­23) bleeds per year. The median (range) number of bleeds per year was significantly lower in patient subgroups without vs. with target joints [0.5 (0.0­17.1) vs. 4.2 (0.0­22.8); P = 0.02] and in those with ≤9 vs. >9 bleeds during the previous 6 months [1.1 (0.0­19.2) vs. 5.3 (0.0­22.8); P = 0.01]. Following randomization to prophylaxis with rFVIII-FS, bleeding frequency was effectively reduced. Absence of target joints and prestudy bleeding frequency were predictors of a low bleeding frequency during prophylaxis treatment.


Assuntos
Fator VIII/administração & dosagem , Hemofilia A/tratamento farmacológico , Sacarose/administração & dosagem , Adolescente , Adulto , Idoso , Criança , Método Duplo-Cego , Esquema de Medicação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
7.
Haemophilia ; 20(1): e15-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24252058

RESUMO

Patients with severe haemophilia A experience frequent and spontaneous bleeding, causing debilitating damage to joints and decreasing quality of life. Prophylaxis with factor VIII (FVIII) reduces joint damage if initiated early. Circulating FVIII levels may be influenced by endogenous von Willebrand factor (VWF), a chaperone protein that binds and stabilizes FVIII. The aim of this study was to determine whether endogenous VWF antigen (VWF:Ag) levels are correlated with FVIII pharmacokinetic (PK) parameters and clinical outcomes in patients with severe haemophilia A. Previously treated, non-inhibitor patients in a multinational, randomized, double-blind, Ph II study received prophylaxis with once-weekly BAY 79-4980 (35 IU kg(-1)) or thrice-weekly recombinant sucrose-formulated FVIII (rFVIII-FS; 25 IU kg(-1)). PK parameters were evaluated at weeks 1 and 26. The number of bleeds per patient during the study was captured as part of the core efficacy endpoint. Spearman rank correlations assessed relationships of VWF:Ag levels with patient age, PK and annualized bleeding rate. Of 131 study patients (aged 13-64 years; BAY 79-4980, n = 63; rFVIII-FS, n = 68), 27 (21%; n = 15 and 12 respectively) were evaluable for PK assessment. Baseline VWF:Ag levels correlated with patient age (P < 0.0001). There was no significant difference in PK results between treatments; thus, PK parameters and VWF levels of all patients were analysed together. AUC(norm) and T1/2 significantly increased with increased VWF:Ag (P < 0.001); clearance significantly decreased with increased VWF:Ag (P = 0.002). Annualized bleeding rate in patients treated with 3× per week rFVIII-FS significantly correlated with VWF:Ag and age (P = 0.038 and 0.021 respectively). PK parameters as well as the clinical outcome significantly correlated with endogenous VWF:Ag. The improved clinical outcome in subjects with high VWF:Ag levels may be explained by VWF:Ag influence on FVIII PK.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/sangue , Hemofilia A/tratamento farmacológico , Hemorragia/metabolismo , Pré-Medicação , Sacarose/uso terapêutico , Fator de von Willebrand/metabolismo , Adolescente , Adulto , Fatores Etários , Idoso , Testes de Coagulação Sanguínea , Esquema de Medicação , Ensaio de Imunoadsorção Enzimática , Fator VIII/administração & dosagem , Hemorragia/sangue , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Sacarose/administração & dosagem , Resultado do Tratamento , Adulto Jovem , Fator de von Willebrand/imunologia
8.
Haemophilia ; 17(4): 625-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21299743

RESUMO

Recent reports have raised concerns regarding potential risk factors for inhibitor development. In Israel, all haemophilia patients (n = 479) are followed by the National Hemophilia Center. Most children are neonatally exposed to factor concentrate (due to circumcision performed at the age of 8 days). The impact of early exposure and recombinant FVIII products (rFVIII) administration (approved in Israel since 1996) upon inhibitor occurrence in our cohort of haemophilia A (HA) patients was analysed. Two hundred ninety-two consecutive paediatric cases with a first symptomatic onset of HA were enrolled and followed over a median time of 7 years [min-max: 9 months to 17 years]. Study endpoint was inhibitor development against factor VIII. In addition, the treatment regimens applied, i.e. bolus administration or 'continuous infusion' and the family history of inhibitor development were investigated. During the follow-up period 31/292 children (10.6%) developed high titre inhibitors. Inhibitors occurred in 14/43 (32.5%) HA patients neonatally exposed to rFVIII, as compared to 22/249 previously treated with Plasma Derived (PD) products (8.8%). The odds ratio for inhibitor formation in rFVIII treated HA patients was 3.43 (95% CI: 1.36-8.65). Transient inhibitor evolved among 2/43 paediatric HA patients, only among those treated with rFVIII. The risk of inhibitor detection significantly increased among HA children treated by continuous infusion (P = 0.025). Our experience shows that the risk of inhibitor formation may be increased by early exposure to recombinant concentrates. The multiple variables affecting inhibitor incidence deserve further attention by larger prospective studies.


Assuntos
Autoanticorpos/sangue , Inibidores dos Fatores de Coagulação Sanguínea/metabolismo , Fator VIII/efeitos adversos , Hemofilia A/tratamento farmacológico , Hemofilia A/imunologia , Proteínas Recombinantes/efeitos adversos , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Fator VIII/uso terapêutico , Feminino , Humanos , Lactente , Israel , Masculino , Proteínas Recombinantes/uso terapêutico
10.
J Thromb Haemost ; 5(2): 378-86, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17083647

RESUMO

BACKGROUND: Bernard-Soulier syndrome (BSS) is a severe inherited bleeding disorder that is caused by a defect in glycoprotein (GP)Ib-IX-V complex, the platelet membrane receptor for von Willebrand factor. PATIENTS: The diagnosis of BSS was made in two members of a Bukharian Jewish family who had life-long thrombocytopenia associated with mucocutaneous bleeding manifestations. METHODS AND RESULTS: Flow cytometry and Western blot analyses showed only trace amounts of GPIb and GPIX on the patients' platelets. Sequence analysis of the GPIbalpha gene revealed a homozygous T > G transversion at nucleotide 709 predicting Trp207Gly substitution in the mature protein. Introduction of the mutation into a mammalian expression construct abolished the surface expression of GPIbalpha in transfected baby hamster kidney cells. The crystal structure of the N-terminus of GPIbalpha (PDB: 1SQ0) indicates that Trp207 is completely buried and located in a disulfide loop structure that interacts with the leucine-rich repeat (LRR) domain. CONCLUSION: A novel mutation, Trp207Gly, causes BSS and predicts disruption of the interaction between a disulfide loop and the LRR domain that is essential for the integrity of GPIbalpha structure.


Assuntos
Síndrome de Bernard-Soulier/genética , Leucina , Mutação de Sentido Incorreto , Complexo Glicoproteico GPIb-IX de Plaquetas/química , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Dobramento de Proteína , Adolescente , Motivos de Aminoácidos , Síndrome de Bernard-Soulier/etiologia , Plaquetas/química , Criança , Clonagem Molecular , Cristalografia por Raios X , Feminino , Hemorragia , Humanos , Judeus , Linhagem , Complexo Glicoproteico GPIb-IX de Plaquetas/análise , Estrutura Terciária de Proteína , Sequências Repetitivas de Ácido Nucleico , Trombocitopenia
11.
Haemophilia ; 12(1): 68-74, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16409178

RESUMO

Haemophilia patients who received non-virucidally treated large pool clotting factors before 1987 have a high rate of chronic hepatitis C viral infection (HCV). Some patients are coinfected with HIV. Haemophilia patients and other coagulation disorders were treated at one centre since the beginning of the 1970, and the Israeli National Hemophilia Center (INHC) was officially founded in 1987. To characterize patients with HCV as well as patients with HCV/HIV coinfection at the INHC. Patients with haemophilia and other coagulation disorders positive for HCV antibodies were evaluated between 2001 and 2004. Demographic data, type and severity of coagulation disorder, frequency of coagulation factor usage and treatment with concentrated clotting factors prior to 1987 were recorded. Liver enzymes, viral load, genotype and data supporting advanced liver disease were evaluated. About 179 of 239 haemophilia patients (75%) tested positive for anti-HCV antibodies. Our cohort consisted of 165 patients in whom clinical, biochemical and virological data were available. About 117 patients had active HCV infection with HCV-RNA-positive, and 27 were HCV/HIV coinfected. Twenty-one patients (13%) persistently tested HCV-RNA-negative, hence were considered to clear their HCV infection. There was no former USSR immigrants among HCV/HIV coinfected compared with HCV-infected or HCV-RNA-negative groups (0 vs. 30% and 38%, respectively; P < 0.001). HCV-RNA-negative patients used concentrated coagulation factor less frequently than HCV or HCV/HIV-infected patients (48% vs. 73%; P = 0.023, and 48% vs. 74%; P = 0.043, respectively). The use of concentrated clotting factors before 1987 was significantly more frequent in HCV/HIV than in either HCV-infected or HCV-RNA-negative patients (96% vs. 49% and 48%, respectively; P < 0.001). Compared with HCV/HIV subjects, patients with HCV monoinfection were characterized by a higher proportion of infection with genotype 1 (80% vs. 61%; P = 0.027). The rate of persistently normal liver enzymes in these patients was higher (24% vs. 7%; P = 0.05) than in the HCV/HIV-coinfected patients. Advanced liver disease was significantly more common in patients with HCV/HIV-coinfection than in HCV-monoinfected patients (11% vs. 3%; P = 0.045). The majority of haemophilia patients are infected with HCV. Viral clearance occurred in a minority of these patients. HCV monoinfected and HCV/HIV coinfected differ clinically and prognostically.


Assuntos
Transtornos da Coagulação Sanguínea/imunologia , Hemofilia A/imunologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/análise , Terapia Antirretroviral de Alta Atividade/métodos , Transtornos da Coagulação Sanguínea/mortalidade , Transtornos da Coagulação Sanguínea/virologia , Estudos de Coortes , Genótipo , Infecções por HIV/imunologia , Infecções por HIV/mortalidade , Infecções por HIV/virologia , Hemofilia A/mortalidade , Hemofilia A/virologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/mortalidade , Hepatite C Crônica/virologia , Humanos , Israel/epidemiologia , Hepatopatias/complicações , Hepatopatias/imunologia , Hepatopatias/virologia , Pessoa de Meia-Idade , Prognóstico , RNA Viral/análise , Carga Viral
12.
Am J Physiol Endocrinol Metab ; 281(1): E190-5, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11404237

RESUMO

We assessed sympathovagal balance in thyrotoxicosis. Fourteen patients with Graves' hyperthyroidism were studied before and after 7 days of treatment with propranolol (40 mg 3 times a day) and in the euthyroid state. Data were compared with those obtained in a group of age-, sex-, and weight-matched controls. Autonomic inputs to the heart were assessed by power spectral analysis of heart rate variability. Systemic exposure to sympathetic neurohormones was estimated on the basis of 24-h urinary catecholamine excretion. The spectral power in the high-frequency domain was considerably reduced in hyperthyroid patients, indicating diminished vagal inputs to the heart. Increased heart rate and mid-frequency/high-frequency power ratio in the presence of reduced total spectral power and increased urinary catecholamine excretion strongly suggest enhanced sympathetic inputs in thyrotoxicosis. All abnormal features of autonomic balance were completely restored to normal in the euthyroid state. beta-Adrenoceptor antagonism reduced heart rate in hyperthyroid patients but did not significantly affect heart rate variability or catecholamine excretion. This is in keeping with the concept of a joint disruption of sympathetic and vagal inputs to the heart underlying changes in heart rate variability. Thus thyrotoxicosis is characterized by profound sympathovagal imbalance, brought about by increased sympathetic activity in the presence of diminished vagal tone.


Assuntos
Hipertireoidismo/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Nervo Vago/fisiopatologia , Adulto , Catecolaminas/urina , Creatinina/urina , Eletrocardiografia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neurotransmissores/urina , Descanso/fisiologia , Decúbito Dorsal/fisiologia , Hormônios Tireóideos/sangue , Tireotropina/sangue
13.
Thyroid ; 11(2): 153-60, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11288984

RESUMO

Hyperthyroidism is associated with a higher incidence of arterial thromboembolism; increasing age, atrial fibrillation, and mitral valve abnormalities are risk factors. However, the contribution of endogenous coagulation parameters is unclear. Because thyroid hormone influences receptor and transcription factors, it can be expected that it will influence proteins involved in coagulation processes synthetised in many cells. Fourteen hyperthyroid patients were studied untreated, after 1 week of treatment with propranolol, and after therapeutic treatment with thiamazol. Fourteen matched controls were used for comparison. On each occasion, endothelial marker proteins, coagulation/fibrinolysis factors, and inflammatory (liver) markers were measured. Excess thyroid hormone was associated with elevated levels of most endothelium-associated proteins. In addition, plasma fibronectin and fibrinogen were increased, while plasminogen was decreased. No evidence was found that hyperthyroidism was associated with coagulation/fibrinolysis activation, or with increased levels of the inflammation markers interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) or C-reactive protein (CRP). Propranolol treatment only lowered the von Willebrand factor propeptide, and slightly increased plasminogen. Treatment with thiamazol returned all parameters to normal. Hyperthyroidism increased the plasma levels of most endothelial marker proteins, and of some liver-synthetized proteins. No evidence for coagulation/fibrinolysis activation was found. However, it appears that endothelial activation, which is indicative of a procoagulant state, is present in hyperthyroidism. This may explain the association between hyperthyroidism and thromboembolism especially if other risk factors are present. von Willebrand factor II (vWF:Ag-II) levels may be suitable markers to evaluate acute changes in endothelial function because this parameter responds more rapidly to changes in endothelial function than other factors.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Antitireóideos/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Hipertireoidismo/tratamento farmacológico , Hipertireoidismo/fisiopatologia , Metimazol/uso terapêutico , Propranolol/uso terapêutico , Adulto , Biomarcadores , Coagulação Sanguínea/fisiologia , Feminino , Fibrinólise/fisiologia , Humanos , Inflamação/metabolismo , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Biossíntese de Proteínas , Proteínas/metabolismo , Valores de Referência
14.
Circulation ; 100(24): 2406-10, 1999 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-10595952

RESUMO

BACKGROUND: Homozygosity for the common (677C-->T) mutation in the methylenetetrahydrofolate reductase (MTHFR) gene is associated with hyperhomocysteinemia, but there is uncertainty as to the association between this mutation and coronary artery disease (CAD). This study examined the association between MTHFR genotypes and age at onset of CAD. METHODS AND RESULTS: Patients (n=169) with documented myocardial infarction or angiographically documented CAD who were aged < or = 55 years at onset of CAD symptoms and DNA samples from control subjects (n=313) were studied. The prevalence of homozygosity among patients with early CAD onset (aged < or = 45 years) was 28%, which was significantly higher than that in patients with later onset (13%) and in control subjects (14%) (odds ratio 2.4, 95% CI 1.24 to 4.69, P=0.006, and odds ratio 2.7, 95% CI 1.15 to 6.42, P=0.01, respectively). Plasma folate was lower in TT homozygotes who had early CAD onset than in those with later onset (P=0.005). Among patients with plasma folate in the lowest quintile (< or = 12.6 nmol/L), 31% were homozygotes, as were 45% of those with low plasma folate and early CAD onset. There was no difference in the prevalence of traditional risk factors among genotypes. The frequency of homozygosity in patients with < or = 1 risk factor was higher than in those with > or = 2 risk factors (30% versus 12%, P<0.05). In multiple regression analysis, TT homozygosity and plasma folate were independently associated with CAD, but the impact of folate was small. CONCLUSIONS: Homozygosity for the 677C-->T mutation of MTHFR is common and is associated with an increased risk of premature CAD in this population.


Assuntos
Doença das Coronárias/enzimologia , Doença das Coronárias/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Idade de Início , Alelos , Doença das Coronárias/epidemiologia , Feminino , Ácido Fólico/sangue , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Homozigoto , Humanos , Israel/epidemiologia , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2) , Pessoa de Meia-Idade , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/genética , Prevalência , Fatores de Risco
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