Episodic replacement of clotting factor concentrates does not prevent bleeding or musculoskeletal damage - the MUSFIH study.

PATIENTS AND METHODS: A longitudinal study was carried out in 255 children from 10 centres in nine developing countries over 5 years to assess the musculoskeletal outcome of children on episodic factor replacement. Outcome was documented by assessment of the annual joint bleeding rate (AJBR), WFH clinical and Pettersson radiological joint scores as well as the FISH score for activities. Of the 203 patients for whom data was available at the end of 5 years, 164 who had received only episodic treatment are included in this report. RESULTS: The median age at the beginning of the study was 10 years (IQR 7-12). The median clotting factor concentrate (CFC) usage was 662 IU kg-1 year-1 (IQ range: 280-1437). The median AJBR was 10 (IQ range: 5-17). The median AJBR was higher in the older children with the median being 5 for the 5 year old child, while it was 9 for the 10 year old and 11 for children older than 15. Given the episodic nature of the replacement therapy, those with a higher AJBR used significantly greater annual CFC doses (P < 0.001); The median change in WFH clinical score and Pettersson radiological score over the 5 years was 0.4/year for each, while the FISH deteriorated at a rate of 0.2/year with poor correlation of these changes with CFC dose. WFH and FISH scores were significantly worse in those with an AJBR of >3 per year (P = 0.001). The change in the Pettersson score was significantly more in those with an AJBR of >5 per year (P = 0.020). Significant changes in FISH scores were only noted after 10 years of age. CONCLUSION: Episodic CFC replacement over a large range of doses does not alter the natural course of bleeding in haemophilia or the musculoskeletal deterioration and should not be recommended as a long term option for treatment. Prophylaxis is the only way to preserve musculoskeletal function in haemophilia.

Process and experience of cross-cultural adaptation of a quality of life measure (CHO-KLAT) for boys with haemophilia in Brazil.

Health-related quality of life (HRQoL) is an important outcome from the perspective of boys with haemophilia and their parents. Few studies have captured the HRQoL of boys with haemophilia in developing countries. This article reports on the cross-cultural adaptation of the Canadian Haemophilia Outcomes - Kids Life Assessment Tool (CHO-KLAT) for use in São Paulo, Brazil. The CHO-KLAT(2.0) was translated into Portuguese, and then translated back into English. The original English and back-translation versions were compared by a group of three clinicians, whose first language was Portuguese. The resulting Portuguese version was assessed through a series of cognitive debriefing interviews with children and their parents. This process identified concepts that were not clear and revised items to ensure appropriate understanding through an iterative process. The initial back-translation was not discrepant from the original English version. We made changes to 66% of the CHO-KLAT(2.0) items based on clinical expert review and 26% of the items based on cognitive debriefings. In addition, two new items were added to the final Portuguese version to reflect the local cultural context. The final result had good face validity. This process was found to be extremely valuable in ensuring the items were accurately interpreted by the boys/parents in São Paulo Brazil. The results suggest that professional translators, clinical experts and cognitive debriefing are all required to achieve a culturally appropriate instrument. The Portuguese CHO-KLAT(2.0) is well understood by Sao Paulo boys/parents. The next step will be to test its validity and reliability locally.

Importance of literacy for self-reported health-related quality of life: a study of boys with haemophilia in Brazil.

Psychosocial outcomes are important in the perspective of boys with haemophilia. However, health-related quality of life (HRQoL) is based on self-report, and assumes adequate literacy. Yet, literacy is rarely assessed prior to data collection. This study sought to identify criteria that might indicate the level of literacy of children being recruited for clinical trials and to develop a simple method to prescreen those whose literacy was uncertain. We developed a brief screening tool in the form of two stories, at a grade 3 reading level, followed by comprehension questions. We applied the screening test to a sample of haemophilic boys between the ages of 7 and 13 years to assess their literacy. The data were analysed to determine the best criteria to use in identifying the ability to independently self-report for HRQoL studies. Twenty-four Brazilian boys (7.9-12.8) completed the testing. The results showed that 17 (70.8%) were literate (were able to both read and comprehend), and could complete a questionnaire without assistance. All boys over 11.0 years of age were sufficiently literate. Grade level was not found to be a helpful criterion. We recommend that all children under the age of 11.0 years be prescreened before providing self-reported HRQoL data. Those with limited literacy should be provided assistance to ensure comprehension of the questions. This is important to ensure high-quality data on HRQoL for future clinical trials.

Transdermal estrogen therapy effects on fibrinogen levels in women with a past history of venous thromboembolism: a pilot study.

OBJECTIVE: To evaluate thromboelastographic parameters and fibrinogen levels in women treated with transdermal 17beta estradiol. METHODS: 29 menopausal women with a history of venous thromboembolic disease were included. Nine patients composed the treatment (HT) group and 20 the control group. Coagulation was assessed by thromboelastography in samples of whole blood and platelet-poor plasma (PPP). The following thromboelastographic variables were measured: time for initial coagulation (R), blood clotting speed (K and the alpha angle), clot tensile strength (MA and G), global index of coagulation (CI) and fibrinolysis (LY30) and fibrinogen levels. RESULTS: There were no differences in the other parameters comparing both groups. Fibrinogen levels showed a 13.77 +/- 19.94% reduction in the HT group and a 5.51 +/- 8.09% increase in the control group after 6 months. CONCLUSIONS: Our data suggested that transdermal estrogen may not increase blood coagulability, but that it reduces fibrinogen levels in HT women.

The role of von Willebrand factor in the hemostatic defect of acute promyelocytic leukemia.

Bleeding complications are often associated with acute promyelocytic leukemia (APL) they occur frequently at the onset of APL and become more serious during chemotherapy. The increased bleeding tendency of APL is caused by a massive proteolytic state, triggered by procoagulant substances, plasminogen activators and proteinases released into the circulation from leukemic cells. The introduction of all-trans-retinoic acid (ATRA) into the treatment of APL has reduced bleeding complications. However the mechanisms of the hemostatic defects in patients with APL and their modifications during ATRA with or without chemotherapy are still incompletely understood. Attempts at characterizing and monitoring these hemostatic abnormalities have been made by using several laboratory parameters. Among them we have studied the structural modifications of von Willebrand Factor (vWF). In APL, plasma vWF is massively degraded, with specific fragments produced by the action of plasmin and elastase. After ATRA therapy, proteolysis diminishes progressively in parallel with the improvement of other hemostatic measurements. We conclude that abnormalities of vWF structure and function might adversely affect hemostasis in APL and that their improvement after ATRA administration might explain in part the effectiveness of this drug in reducing hemorrhagic complications.

An aqueous extract of guaraná (Paullinia cupana) decreases platelet thromboxane synthesis.

The effects of an aqueous extract of guaraná (Paullinia cupana) on rabbit platelet aggregation and thromboxane synthesis were examined. The guaraná extract (100 mg/ml) and fractions separated by TLC (origin and xanthines) decreased platelet aggregation (37, 27 and 31% of control values, respectively) and platelet thromboxane formation from [14C]-arachidonic acid (78, 70 and 50% of control values, respectively). The decreased thromboxane synthesis could be responsible, at least in part, for the antiaggregatory action of guaraná.

Aluminum induces lipid peroxidation and aggregation of human blood platelets.

Aluminum (Al3+) intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacylglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al(3+) -induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL) of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 microM) stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA) (100 microM) and n-propyl gallate (NPG) (100 microM), inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA) (100 microM), an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation.

Determination of serum aluminum, platelet aggregation and lipid peroxidation in hemodialyzed patients.

Aluminum (Al3+) overload is frequently associated with lipid peroxidation and neurological disorders. Aluminum accumulation is also reported to be related to renal impairment, anemia and other clinical complications in hemodialysis patients. The aim of the present study was to determine the degree of lipid peroxidation, platelet aggregation and serum aluminum in patients receiving regular hemodialytic treatment. The level of plasma lipid peroxidation was evaluated on the basis of thiobarbituric acid reactive substances (TBARS). Mean platelet peroxidation in patients undergoing hemodialysis was significantly higher than in normal controls (2.7 +/- 0.03 vs. 1.8 +/- 0.06 nmol/l, P<0.05). Platelet aggregation and serum aluminum levels were determined by a turbidimetric method and atomic absorption spectrophotometry, respectively. Serum aluminum was significantly higher in patients than in normal controls (44.5 +/- 29 vs. 10.8 +/- 2.5 microg/l, P<0.05). Human blood platelets were stimulated with collagen (2.2 microg/ml), adenosine diphosphate (6 microM) and epinephrine (6 microM) and showed reduced function with the three agonists utilized. No correlation between aluminum levels and platelet aggregation or between aluminum and peroxidation was observed in hemodialyzed patients.

Platelet aggregation and lipoprotein levels in a patient with familial hypercholesterolemia after selective LDL-apheresis.

Platelet aggregation was studied in a patient with familial hypercholesterolemia immediately after apheresis selective for low-density lipoprotein (LDL), a lipid-lowering procedure. This treatment reduced plasmatic levels of total and LDL-cholesterol, apo B, and triglyceride. Increased platelet aggregation was reduced immediately after the apheresis in whole blood as well as in platelet-rich plasma. However, aggregation in washed platelets remained unchanged after LDL-apheresis. In conclusion, in this patient reduction of LDL-cholesterol improved platelet function in the very short term.

Effects of conjugated equine estrogens or raloxifene on lipid profile, coagulation and fibrinolysis factors in postmenopausal women.

OBJECTIVES: To compare the effect of conjugated equine estrogens (CEE) and raloxifene on lipid profile and hemostasis. MATERIALS AND METHODS: A double-blind, randomized and parallel study was performed with 90 healthy postmenopausal women, aged 54 +/- 5 years, divided into three groups and submitted to daily therapy with either CEE 0.625 mg, raloxifene 60 mg or placebo for 4 months. The lipid profile, coagulation and fibrinolytic factors were analyzed. RESULTS: CEE increased the levels of high density lipoprotein cholesterol (HDL-C) from 49.0 to 56.8 mg/dl (p < 0.001), very low density lipoprotein cholesterol (VLDL-C) from 17.2 to 22.3 mg/dl (p < 0.001), and triglycerides from 86.0 to 111.7 mg/dl (p < 0.001), and decreased the levels of low density lipoprotein cholesterol (LDL-C) from 121.0 to 106.5 mg/dl (p < 0.001). The only significant effect of raloxifene was an increase in the levels of HDL-C from 46.0 to 47.8 mg/dl (p = 0.019). There was no significant reduction in LDL-C, from 115.5 to 110.2 mg/dl (p = 0.06), VLDL-C, from 21.7 to 20.0 mg/dl (p = 0.201), and triglycerides, from 108 to 100 mg/dl (p = 0.201). CEE decreased the levels of fibrinogen, from 370.5 to 326.8 g/l (p = 0.039) and the levels of antithrombin III, from 99.5 to 93.2% (p < 0.001). Raloxifene decreased the levels of fibrinogen, from 354.7 to 302.0 g/l (p = 0.009) and the levels of antithrombin III, from 102.4 to 98.5% (p = 0.039). CEE increased levels of protein C from 103.7 to 115.3 mg/l (p < 0.001) and raloxifene did not change the levels of protein C (107.9 to 105.1 mg/l; p = 0.158). CEE decreased the antigen levels of tissue plasminogen activator (t-PA) from 8.8 to 6.8 U/ml (p < 0.001), and of plasminogen activator inhibitor (PAI-1) from 30.8 to 21.6 U/ml (p < 0.010), whereas raloxifene had no significant effect on either t-PA, from 9.6 to 9.2 U/ml (p = 0.235) or PAI-1 antigen levels, from 32.1 to 30.4 U/ml (p = 0.538). CONCLUSION Both CEE and raloxifene exert significant effects on the lipid and coagulation profile. CEE had a more significant effect on fibrinolysis than raloxifene. These effects may have a significant impact on the cardiovascular risk that needs to be confirmed in larger studies.

Effects of catechins on human blood platelet aggregation and lipid peroxidation.

The activity of catechins was studied for inhibitory activity in human blood platelets. Platelet aggregation and peroxidation were evaluated in platelet rich plasma (PRP) obtained from samples of healthy volunteers. Human blood platelets were submitted to stimulation with 300 microM arachidonic acid, 3 microM adenosine diphospate (ADP) and 6 microM epinephrine. Treatment with (200 microg/mL) catechin or epicatechin was sufficient to exhibit a potent inhibitory effect of the three agents. The inhibitory effect was dose dependent at concentrations of 20-200 microg/mL. Using malondialdehyde (MDA) as an index of total lipid peroxidation capacity, decreased production of MDA of the platelets treated with catechin or epicatechin after stimulation by arachidonic acid was observed. These findings suggest that catechins protect platelets from peroxidative stress and their aggregation.

Oxidized low-density lipoprotein stimulates nitric oxide release by rabbit aortic endothelial cells.

Incubation of rabbit aortic endothelial cells (RAEC) with oxidized low-density lipoprotein (LDL) for 16 h resulted in stimulation of calcium uptake and increased release of nitric oxide (NO) by these cells. Accompanying inhibition of protein tyrosine phosphatase (PTP) activity in these cells was also observed. Conversely, native LDL was unable to produce any of those effects. These observations suggest that oxidized LDL could modulate two major signalling processes in endothelial cells: tyrosine dephosphorylation and NO synthesis. Such modulation may be of importance in the early phase of the atherogenic process.

Antiphospholipid antibodies and antiphospholipid syndrome in 57 children and adolescents with systemic lupus erythematosus.

The presence of antiphospholipid (aPL) antibodies and antiphospholipid syndrome (APS) was researched in 57 children and adolescents with systemic lupus erythematosus (SLE). The frequency of aPL antibodies was 75.4% (anticardiolipin 70.2% and lupus anticoagulant 29.1%). The positivity for these antibodies fluctuated during the course of the disease. No association was found between aPL antibodies and clinical or laboratory manifestations or the autoantibodies studied, nor with the activity or gravity of the SLE. APS was diagnosed in 14% of the cases (eight patients), on average three years after the diagnosis of SLE. Four patients had arterial thrombosis (stroke, three; transient ischaemic attack, one; amaurosis fugax, two; renal, one), one presented with deep vein thrombosis (DVT) and three had involvement of small calibre vessels (osteonecrosis, two; transverse myelitis, one). Recurrences were observed in three of the eight cases (37.5%), with a mean interval of 13 months between the events. The presence of APS was associated with haemolytic anaemia, leukopenia, thrombocytopenia, coagulation abnormalities, ischaemic cerebrovascular accidents, amaurosis fugax, osteonecrosis and interstitial pneumonitis. A negative association was observed between APS and the presence of anti-Ro antibodies.

Avaliação do alinhamento postural e do desempenho em atividades funcionais de crianças hemofílicas em idade inferior a sete anos, com e sem sinovite crônica: correlação com a incidência de hemartroses / Evaluation of postural alignment and performance in functional activities among hemophilic children under 7 years old with and without chronic synovitis: correlation with hemarthrosis incidence

INTRODUÇÃO: A sinovite na hemofilia pode induzir às alterações nos receptores sensitivos e proprioceptivos articulares. Tal efeito favorece a redução de estabilidade e um desalinhamento corporal, podendo comprometer a funcionalidade das crianças acometidas. OBJETIVO: Avaliar o alinhamento postural dos membros inferiores e o desempenho funcional de crianças hemofílicas, relacionando-os com a incidência de hemartroses. MÉTODO: Foi avaliado um grupo experimental (GE) de 28 crianças hemofílicas e um grupo controle (GC) de 20 crianças sem hemofilia. O GE foi dividido de acordo com o grau de comprometimento articular: 16 crianças no grupo sem sinovite crônica (GSS) e 12 no grupo com sinovite crônica (GCS). Cada grupo foi subdividido por faixa etária: 3-4 anos, 5-6 anos, 7 anos. A avaliação consistiu da análise do alinhamento dos ângulos do joelho e do tornozelo através do programa Geometer Sketchpad. O desempenho das atividades funcionais foi avaliado através de testes modificados a partir do Exame Neurológico Evolutivo de Lefévre. RESULTADOS: Foi constatado que a média dos sangramentos dos hemofílicos aumenta com a idade (p< 0,001) e parece ser relacionada com o grau de comprometimento articular (GCS>GSS), (p< 0,059); o ângulo do joelho do GCS tende a um menor valor (semiflexão) quando comparado aos outros grupos; e há diferença significativa no percentual de desempenho nos testes entre grupos na faixa etária de 7 anos (GSS>GC e GSS>GCS), (p< 0,087). DISCUSSÃO E CONCLUSÃO: Crianças hemofílicas de 7 anos apresentaram menor desempenho funcional quando comparadas aos outros grupos. Este resultado ressalta a importância da fisioterapia precoce associada à terapêutica médica para evitar comprometimentos articulares severos.

Determination of serum aluminum, platelet aggregation and lipid peroxidation in hemodialyzed patients

Aluminum (Al3+) overload is frequently associated with lipid peroxidation and neurological disorders. Aluminum accumulation is also reported to be related to renal impairment, anemia and other clinical complications in hemodialysis patients. The aim of the present study was to determine the degree of lipid peroxidation, platelet aggregation and serum aluminum in patients receiving regular hemodialytic treatment. The level of plasma lipid peroxidation was evaluated on the basis of thiobarbituric acid reactive substances (TBARS). Mean platelet peroxidation in patients undergoing hemodialysis was significantly higher than in normal controls (2.7 ± 0.03 vs 1.8 ± 0.06 nmol/l, P<0.05). Platelet aggregation and serum aluminum levels were determined by a turbidimetric method and atomic absorption spectrophotometry, respectively. Serum aluminum was significantly higher in patients than in normal controls (44.5 ± 29 vs 10.8 ± 2.5 æg/l, P<0.05). Human blood platelets were stimulated with collagen (2.2 æg/ml), adenosine diphosphate (6 æM) and epinephrine (6 æM) and showed reduced function with the three agonists utilized. No correlation between aluminum levels and platelet aggregation or between aluminum and peroxidation was observed in hemodialyzed patients

Aluminum induces lipid peroxidation and aggregation of human blood platelets

Aluminum (Al3+) intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacyglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al3+-induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL) of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 muM) stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA) (100 muM) and n-propyl gallate (NPG) (100 muM), inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA) (100 muM), an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation.