Late Outcome of a Randomized Study on Oral Magnesium for Premature Complexes / Evolução Tardia de Estudo Randomizado com Uso de Magnésio Via Oral em Extrassístoles Sintomáticas

Background: Ventricular and supraventricular premature complexes (PC) are frequent and usually symptomatic. According to a previous study, magnesium pidolate (MgP) administration to symptomatic patients can improve the PC density and symptoms. Objective: To assess the late follow-up of that clinical intervention in patients treated with MgP or placebo. Methods: In the first phase of the study, 90 symptomatic and consecutive patients with PC were randomized (double-blind) to receive either MgP or placebo for 30 days. Monthly follow-up visits were conducted for 15 months to assess symptoms and control electrolytes. 24-hour Holter was performed twice, regardless of symptoms, or whenever symptoms were present. In the second phase of the study, relapsing patients, who had received MgP or placebo (crossing-over) in the first phase, were treated with MgP according to the same protocol. Results: Of the 45 patients initially treated with MgP, 17 (37.8%) relapsed during the 15-month follow-up, and the relapse time varied. Relapsing patients treated again had a statistically significant reduction in the PC density of 138.25/hour (p < 0.001). The crossing-over patients reduced it by 247/hour (p < 0.001). Patients who did not relapse, had a low PC frequency (3 PC/hour). Retreated patients had a 76.5% improvement in symptom, and crossing-over patients, 71.4%. Conclusion: Some patients on MgP had relapse of symptoms and PC, indicating that MgP is neither a definitive nor a curative treatment for late follow-up. However, improvement in the PC frequency and symptoms was observed in the second phase of treatment, similar to the response in the first phase of treatment. .

Fundamento: Extrassístoles (ES) ventriculares e supraventriculares são frequentes e muitas vezes sintomáticas. Segundo estudo prévio, a administração de pidolato de magnésio (PMg) a pacientes sintomáticos pode resultar na melhora da densidade das ES e dos sintomas relacionados. Objetivo: Avaliar os resultados dessa intervenção clínica inicial no seguimento tardio de pacientes recebendo PMg ou placebo. Métodos: Noventa pacientes com ES, sintomáticos e consecutivos foram randomizados (duplo-cego) para receber PMg ou placebo por 30 dias. Visitas mensais de seguimento (15 meses) foram realizadas para avaliar a sintomatologia e controlar eletrólitos. O Holter de 24 horas foi realizado sempre que sintomáticos, ou duas vezes, independentemente dos sintomas. Na segunda fase do estudo, os pacientes cujos sintomas recidivassem, seja do grupo PMg ou placebo (crossing over), receberam PMg seguindo-se o mesmo protocolo. Resultados: Dos 45 pacientes que receberam inicialmente o PMg, 17 (37,8%) apresentaram recidiva dos sintomas em tempo variável nos 15 meses. Os pacientes com recidiva e tratados uma segunda vez apresentaram redução estatisticamente significante na densidade de ES de 138,25/hora (p < 0,001). Os pacientes de crossing reduziram em 247/hora (p < 0,001). Nos pacientes que não apresentaram recidiva, a frequência de ES foi baixa (3 ES/hora). A melhora dos sintomas foi de 76,5% nos retratados e de 71,4% nos de crossing. Conclusão: Houve recorrência de sintomas e das ES em alguns pacientes que usaram PMg, deixando claro não ser essa uma forma de tratamento definitivo ou curativo no seguimento tardio. Contudo, houve também melhora na frequência de ES e de sintomas em uma segunda etapa de tratamento, semelhante à resposta na primeira etapa. .

Late outcome of a randomized study on oral magnesium for premature complexes.

BACKGROUND: Ventricular and supraventricular premature complexes (PC) are frequent and usually symptomatic. According to a previous study, magnesium pidolate (MgP) administration to symptomatic patients can improve the PC density and symptoms. OBJECTIVE: To assess the late follow-up of that clinical intervention in patients treated with MgP or placebo. METHODS: In the first phase of the study, 90 symptomatic and consecutive patients with PC were randomized (double-blind) to receive either MgP or placebo for 30 days. Monthly follow-up visits were conducted for 15 months to assess symptoms and control electrolytes. 24-hour Holter was performed twice, regardless of symptoms, or whenever symptoms were present. In the second phase of the study, relapsing patients, who had received MgP or placebo (crossing-over) in the first phase, were treated with MgP according to the same protocol. RESULTS: Of the 45 patients initially treated with MgP, 17 (37.8%) relapsed during the 15-month follow-up, and the relapse time varied. Relapsing patients treated again had a statistically significant reduction in the PC density of 138.25/hour (p < 0.001). The crossing-over patients reduced it by 247/hour (p < 0.001). Patients who did not relapse, had a low PC frequency (3 PC/hour). Retreated patients had a 76.5% improvement in symptom, and crossing-over patients, 71.4%. CONCLUSION: Some patients on MgP had relapse of symptoms and PC, indicating that MgP is neither a definitive nor a curative treatment for late follow-up. However, improvement in the PC frequency and symptoms was observed in the second phase of treatment, similar to the response in the first phase of treatment.

Redução da densidade de extrassístoles e dos sintomas relacionados após administração de magnésio por via oral / Successful improvement of frequency and symptoms of premature complexes after oral magnesium administration

FUNDAMENTO: As extrassístoles ventriculares e supraventriculares (EV e ESSV) são frequentes e muitas vezes sintomáticas. O íon magnésio (Mg) desempenha um papel importante na fisiologia do potencial de ação transmembrana celular e do ritmo cardíaco. OBJETIVO: Avaliar se a administração do pidolato de magnésio (PMg) em pacientes com EV e ESSV tem desempenho superior ao uso do placebo (P) na melhora dos sintomas e densidade das extrassístoles (DES). MÉTODOS: Estudo duplo-cego, randomizado, com 60 pacientes sintomáticos consecutivos, com mais de 240/EV ou ESSV ao Holter de 24 horas e selecionados para receber P ou PMg. Para avaliar a melhora da sintomatologia, foi feito um questionário categórico e específico de sintomas relacionados às extrassístoles. Após o tratamento, foi considerada significante uma redução de mais de 70% na DES por hora. A dose do PMg foi de 3,0 g/dia por 30 dias, equivalente a 260 mg do elemento Mg. Nenhum paciente tinha cardiopatia estrutural ou insuficiência renal. RESULTADOS: Dos 60 pacientes estudados, 33 eram do sexo feminino (55%). A faixa etária variou de 16 a 70 anos. No grupo PMg, 76,6% dos pacientes tiveram redução maior que 70%, 10% deles maior que 50% e somente 13,4% tiveram redução menor que 50% na DES. No grupo P, 40% dos pacientes tiveram melhora de apenas 30% na frequência de extrassístoles (p < 0,001). A melhora dos sintomas foi alcançada em 93,3% dos pacientes do grupo PMg, comparada com somente 16,7% do grupo P (p < 0,001). CONCLUSÃO: A suplementação de Mg via oral reduziu a DES, resultando em melhora dos sintomas.

BACKGROUND: Premature ventricular and supraventricular complexes (PVC and PsVC) are frequent and often symptomatic. The magnesium (Mg) ion plays a role in the physiology of cell membranes and cardiac rhythm. OBJECTIVE:We evaluated whether the administration of Mg Pidolate (MgP) in patients with PVC and PsVC is superior to placebo (P) in improving symptoms and arrhythmia frequency. METHODS: Randomized double-blind study with 60 consecutive symptomatic patients with more than 240 PVC or PsVC on 24-hour Holter monitoring who were selected to receive placebo or MgP. To evaluate symptom improvement, a categorical and a specific questionnaire for symptoms related to PVC and PsVC was made. Improvement in premature complex density (PCD) per hour was considered significant if percentage reduction was >70% after treatment. The dose of MgP was 3.0 g/day for 30 days, equivalent to 260mg of Mg element. None of the patients had structural heart disease or renal failure. RESULTS: Of the 60 patients, 33 were female (55%). Ages ranged from 16 to 70 years old. In the MgP group, 76.6% of patients had a PCD reduction >70%, 10% of them >50% and only 13.4% <50%. In the P group, 40% showed slight improvement, <30%, in the premature complexes frequency (p < 0.001). Symptom improvement was achieved in 93.3% of patients in the MgP group, compared with only 16.7% in the P group (p < 0.001). CONCLUSION: Oral Mg supplementation decreases PCD, resulting in symptom improvement.

Successful improvement of frequency and symptoms of premature complexes after oral magnesium administration.

BACKGROUND: Premature ventricular and supraventricular complexes (PVC and PsVC) are frequent and often symptomatic. The magnesium (Mg) ion plays a role in the physiology of cell membranes and cardiac rhythm. OBJECTIVE: We evaluated whether the administration of Mg Pidolate (MgP) in patients with PVC and PsVC is superior to placebo (P) in improving symptoms and arrhythmia frequency. METHODS: Randomized double-blind study with 60 consecutive symptomatic patients with more than 240 PVC or PsVC on 24-hour Holter monitoring who were selected to receive placebo (P) or MgP. To evaluate symptom improvement, a categorical and a specific questionnaire for symptoms related to PVC and PsVC was made. Improvement in premature complex density (PCD) per hour was considered significant if percentage reduction was >70% after treatment. The dose of MgP was 3.0 g/day for 30 days, equivalent to 260 mg of Mg element. Any patient had structural heart disease or renal failure. RESULTS: Of the 60 patients, 33 were female (55%). Ages ranged from 16 to 70 years old. In the MgP group, 76.6% of patients had a PCD reduction >70%, 10% of them >50% and only 13.4% <50%. In the P group, 40% showed slight improvement, <30%, in the PC frequency (p < 0.001). Symptom improvement was achieved in 93.3% of patients in the MgP group, compared with only 16.7% in the P group (p < 0.001). CONCLUSION: Oral Mg supplementation decreases PCD, resulting in symptom improvement.

Redução da densidade de extrassístoles e dos sintomas relacionados após administração de magnésio por via oral / Successful improvement of frequency and symptoms of premature complexes after oral Magnesium administration

Introdução: As extrassístoles ventriculares e supraventriculares (EV e ESSV) são frequentes e muitas vezes sintomáticas. O íon magnésio (Mg) desempenha um papel importante na fisiologia do potencial de ação transmembrana celular e do ritmo cardíaco. Objetivo: Avaliar se a administração do Pidolato de Magnésio (PMg) em pacientes com EV e ESSV é superior ao placebo (P) na melhora dos sintomas e densidade das extrassístoles(DES). Métodos: Estudo duplo-cego, randomizado, com 90 pacientes sintomáticos consecutivos, com mais de 240/EV ou ESSV ao Holter de 24 horas e selecionados para receber P ou PMg. Para avaliar a melhora da sintomatologia, foi feito um questionário categórico e específico de sintomas relacionado às extrassístoles. Foi considerada significante uma redução de mais de 70% na DES por hora após o tratamento. A dose do PMg foi de 3,0g/dia por 30 dias, equivalente a 260mg do elemento Mg. Nenhum paciente tinha cardiopatia estrutural ou insuficiência renal. Resultados: Dos 90 pacientes estudados, 49 eram do sexo feminino (54,4%). A faixa etária variou de 16 a 70 anos. No grupo PMg, 77,8% dos pacientes tiveram redução maior que 70%, 6,7% deles entre 50% a 70% e, somente 13,3% dos pacientes com redução menor que 50% na DES . No grupo P, 44,4% dos pacientes tiveram melhora de apenas 30% na frequência de extrassístoles (p<0,001). A melhora dos sintomas foi alcançada em 91,1% dos pacientes do grupo PMg, comparada com somente 15,6% do grupo P(p<0,001). Conclusão: A suplementação de Mg por via oral reduziu a DES, resultando em melhora dos sintomas. Estudos clínicos e moleculares são necessários para avaliar o Mg intracelular e orientar quanto às necessidades diárias deste íon, evidenciar as prováveis deficiências e esclarecer melhor como prevenir e tratar pacientes com extrassístoles sintomáticas e sem cardiopatia estrutural.

Introduction: Premature ventricular and supraventricular complexes (PVC and PsVC) are frequent and often symptomatic. The magnesium (Mg) ion plays a role in the physiology of cell membranes and cardiac rhythm. Objective: We evaluated whether the administration of Mg Pidolate (MgP) in patients with PVC and PsVC is superior to placebo (P) in improving symptoms and arrhythmia frequency. Methods: Randomized double-blind study with 90 consecutive symptomatic patients with more than 240 PVC or PsVC on 24-hour Holter monitoring who were selected to receive placebo or MgP. To evaluate symptom improvement, a categorical and a specific questionnaire for symptoms related to PVC and PsVC was made. Improvement in premature complex density (PCD) per hour was considered significant if percentage reduction was >=70% after treatment. The dose of MgP was 3.0 g/day for 30 days, equivalent to 260mg of Mg element. None of the patients had structural heart disease or renal failure. Results: Of the 90 patients, 49 were female (54,4%). Ages ranged from 16 to 70 years old. In the MgP group, 77.8% of patients had a PCD reduction >70%, 6,7% of them from 50% to 70%, and only 13.3% <50%. In the P group, 44,4% showed slight improvement, <30%, in the premature complexes frequency (p<0.001). Symptom improvement was achieved in 91.1% of patients in the MgP group, compared with only 15.6% in the P group (p<0.001). Conclusions: Oral Mg supplementation decreases PCD, resulting in symptom improvement. Clinical and molecular studies are needed to evaluate intracellular Mg and develop better targets for the daily needs of this ion, show probable deficiencies, and explain how to prevent and better treat patients with symptomatic premature ventricular, and supraventricular complexes and no apparent heart disease.

Influence of lipids and obesity on haemorheological parameters in patients with deep vein thrombosis.

It is not well established whether haemorheological alterations constitute independent risk factors for deep vein thrombosis (DVT). We have determined in 149 DVT patients and in 185 control subjects the body mass index (BMI), the haemorheological profile: blood viscosity (BV), plasma viscosity (PV), fibrinogen (Fg), erythrocyte aggregation (EA), erythrocyte deformability (ED) and plasma lipids. In the crude analysis BMI, Fg, PV, EA, triglycerides (TG) and ApoB were statistically higher and HDL cholesterol (HDL-Chol) statistically lower in DVT patients than in controls. No differences in BV and ED were observed. After BMI adjustment, Fg, PV and EA remained statistically higher in DVT cases than in controls (P = 0.013; P = 0.012; P = 0.013; P = 0.028, respectively). When the risk of DVT associated with these variables (using cut-offs that corresponded to the mean plus one SD of the control group) was estimated, EA > 8.2 and PV > 1.28 mPa . s were significantly associated with DVT even further adjustment for lipids and obesity (OR = 2.78, P = 0.004; OR = 1.91, P = 0.024, respectively). However, PV did not remain statistically significant after additional adjustment for Fg. When we consider together all the analyzed variables in order to control every variable for each other, TG > 175 mg/dl (OR = 3,2, P = 0.004) and BMI > 30 kg/m(2) (OR = 3.5, P = 0.003), were also independently associated with a greater risk of DVT. Our results suggest that increased EA constitute an independent risk factor for DVT. However, when associated to hyperlipidaemia and obesity it further increases thrombotic risk.

Lipoprotein (a) in young individuals as a marker of the presence of ischemic heart disease and the severity of coronary lesions.

The purpose of this study was to evaluate whether high levels and small isoforms of lipoprotein (a) [Lp(a)] are markers of risk of early myocardial infarction and markers of the severity of coronary atherosclerosis. Lp(a) levels and small apo(a) isoforms were higher in 222 patients than in 199 controls (p<0.001). In patients, Lp(a)> or =30 mg/dL was associated with the presence of coronary lesions (p=0.007) and the severity of coronary atherosclerosis (p=0.002). The present study suggests that Lp(a) levels and small isoforms are markers of early myocardial infarction and that Lp(a) levels > or =30 mg/dL are associated with severe patterns of coronary atherosclerosis.

Influence of fibrinogen levels on erythrocyte aggregation determined with the Myrenne aggregometer and the Sefam erythro-aggregometer.

Fibrinogen is one of the plasmatic proteins which has a major influence on erythrocyte aggregation. The level of fibrinogen at which erythrocyte aggregation does not further increase is not well established. Therefore we aim to determine erythrocyte aggregation with two devices: Myrenne aggregometer (M0 and M1) and Sefam erythro-aggregometer (Ta, AI10 and gammaD) in relation with fibrinogen levels, in patients with several diseases with fibrinogen levels ranging between 200-1100 mg/dl. With the Myrenne aggregometer a plateau can be observed for fibrinogen levels higher than 400 mg/dl, while with the Sefam erythro-aggregometer, aggregation increases proportionally with fibrinogen levels higher than 400 mg/dl. In addition, for fibrinogen values higher than 400 mg/dl, only statististically significant correlations could be observed between fibrinogen and erythrocyte aggregation parameters with the Sefam erythro-aggregometer: r(Ta)=-0.463; r(AI10)=0.624, r(gammaD)=0.817, p<0.01, but not with the Myrenne: r(M0)=0.01, r(M1)=0.02, ns. Although the Sefam erythro-aggregometer is a better tool for determining erythrocyte aggregation both at low and high fibrinogen levels, the Myrenne aggregometer may be useful for assessing the erythrocyte aggregation as an indicator of cardiovascular risk, as in such circumstances fibrinogen levels do not usually exceed values higher than 400 mg/dl.

Effect of a hypocaloric diet on lipids and rheological profile in subjects with severe and morbid obesity. A follow-up study.

Discrepant results have been published regarding modifications of rheological parameters in obese subjects after a low caloric diet (LCD). In order to ascertain whether a decrease in BMI associated to a LCD, is accompanied by changes in the hemorheological parameters, we determined in 41 morbid obese subjects (32 female, 9 male aged 33+/-10 years) BMI, glucose, plasmatic lipids and apolipoproteins, fibrinogen, blood viscosity (Brookfield viscosimeter), plasma viscosity (Fresenius capillary viscosimeter), erythrocyte aggregation (Myrenne aggregometer), hematocrit and erythrocyte indexes, before starting on a LCD and 1 and 3 months after. During the first month obese subjects received a very low caloric diet (VLCD) (Modifast) providing 458 kcal per day. The second and third month they received a LCD providing 1500 kcal/day for men and 1200 kcal/day for women. One month after starting on a VLCD, a statistical significant decrease in glucose (p<0.001), Total-cholesterol (p<0.001), LDL-cholesterol (p<0.001), triglycerides (p=0.012), apoB (p<0.001) and erythrocyte aggregation (p<0.001) were observed together with a concomitant decrease in BMI (p<0.001). The expected decrease in HDL-cholesterol associated with a low fat diet was also noted in these individuals. No changes in fibrinogen, hematocrit, blood viscosity or plasma viscosity were observed. At 3 months only a slight increase in BMI was observed regarding the one month period, glucose being the only parameter which remained statistically lower. All the other significant parameters returned to their basal values at 3 months. VLCD (Modifast) is associated to a significant decrease in BMI with the corresponding improvement in glucose, lipids and erythrocyte aggregation at one month. However a LCD alone does not produce a further decrease in weight and both lipids and erythrocyte aggregation return to the basal situation at three months.

Rheological profile in severe and morbid obesity. Preliminary results.

The association of hemorheological alterations with morbid obesity remains a question of debate. In order to ascertain whether morbid obese subjects show certain hemorheological alterations which might be involved in the higher thrombotic risk which characterizes these subjects, we determine glucose, plasma lipids, apolipoproteins, fibrinogen, hematocrit, blood viscosity (Brookfield DVIII viscosimeter), both at native and corrected hematocrit of 45%, plasma viscosity (Fresenius capillary viscosimeter), erythrocyte aggregation (Myrenne aggregometer), both at stasis and at 3 s(-1) at 45% hematocrit and erythrocyte indexes in 41 morbid obese subjects (32 female, 9 male aged 33+/-10 years), and in a well matched non-obese control group (40 female, 15 male, aged 32+/-10 years). Mean BMI in the morbid obese group was 44.9+/-6.7 kg/m2 vs 23.5+/-4.8 kg/m2 in the control group (p<0.001). Morbid obese subjects when compared with the control group showed a statistically higher glucose level (p<0.001), LDL-cholesterol (p=0.019), triglycerides (p<0.001), apoB (p=0.019), apoB/A1 (p<0.001), fibrinogen (p<0.001), erythrocyte aggregation (p<0.001), and a statistically lower HDL-cholesterol (p<0.001). No differences between both groups were observed regarding total-cholesterol, plasma viscosity, blood viscosity and hematocrit (p=0.109; p=0.690; p=0.510; p=0.950), respectively. After the adjustment for BMI, differences in glucose, LDL-cholesterol, triglycerides, apoB, apoB/A1, and erythrocyte aggregation did not reach the statistical significance, and differences in fibrinogen were borderline significant (p=0.051), showing a direct effect of BMI on the detected differences between obese and non-obese. Our results suggest that in morbid obese subjects the increased fibrinogen levels and the altered lipid profile associated with their higher BMI, could in addition to its known mechanisms on haemostasis, favour both venous and arterial thrombotic events by enhancing erythrocyte aggregation.

Influence of plasma and erythrocyte factors on red blood cell aggregation in survivors of acute myocardial infarction.

Increased erythrocyte aggregation (EA) has been observed in patients with ischaemic heart disease (IHD), although most of these studies have been performed in the acute phase when reactant proteins may account for this increase. Little is known about the role played by the erythrocyte itself in this aggregation process. To ascertain the contribution of both plasma and erythrocyte factors to EA in IHD, we investigated the following parameters in 78 survivors of acute myocardial infarction (AMI) and in a well-matched control group of 98 subjects: EA, glucose, total cholesterol (T-Chol), low-density lipoprotein-cholesterol (LDL-Chol), high-density lipoprotein-cholesterol (HDL-Chol), triglycerides, apolipoproteins A(1) and B, protein and functional fibrinogen, plasma sialic acid, membrane sialic acid, and the cholesterol and phospholipid content of the erythrocyte membrane. AMI survivors showed higher glucose (p<0.001), a borderline increase in triglycerides (p = 0.043), and a statistical decrease in Apo A(1) (p= 0.003) relative to controls. EA, functional fibrinogen, and plasma sialic acid were statistically higher in AMI survivors than in controls (p= 0.001; p<0.001; p= 0.011, respectively). Membrane sialic acid content was statistically lower in AMI patients than in controls (p= 0.026). No differences were observed in either membrane cholesterol or phospholipids. Multivariate logistic regression analysis, in which EA was dichotomized as higher or lower than 8.7, demonstrated that triglyceride levels higher than 175 mg/dL (OR= 7.7, p= 0.001) and functional fibrinogen levels higher than 320 mg/dL (OR= 3.7, p= 0.004) were independently associated with a greater risk of erythrocyte hyperaggregability. Our results suggest that plasma lipids, predominantly triglycerides, and fibrinogen may not only enhance the development of ischaemic events by their recognized atherogenic mechanisms, but also by increasing EA.

Erythrocyte aggregation determined with the Myrenne aggregometer at two modes (M0, M1) and at two times (5 and 10 sec).

Erythrocyte aggregation index determined with the Myrenne aggregometer gives a wide range of values both in healthy and disease, as observed in the literature, making results less comparable. This is due to the fact that it gives two aggregation indexes depending on the rotation speed of the cone, M0 (at stasis) and M1 (at 3 s(-1)) and time elapsed (5 or 10 sec), after the cone is stopped abruptly. We determined in 112 healthy volunteers both indexes at two modes and at two times, along with fibrinogen, plasmatic lipids and hematimetric indexes. The correlations between both the 5 and 10 sec mode, and the different variables were analysed and although a statistically significant correlation was observed in both modes, M1 at 5 sec gave the highest correlation values: 0.445, 0.485, 0.364, 0.460 for T-Chol, LDL-Chol, Apo B/A1 and fibrinogen, respectively; p<0.01. Therefore, we suggest that all the erythrocyte aggregation measurements should be performed at a hematocrit adjusted to 45%, with autologous plasma, and that an aggregation time of 5 sec (as opposed to 10 sec) should be used in order to avoid confusion and misunderstanding and to allow for comparability of results with the de Myrenne aggregometer between laboratories.

Thrombin-activatable fibrinolysis inhibitor in young patients with myocardial infarction and its relationship with the fibrinolytic function and the protein C system.

Thrombin-activatable fibrinolysis inhibitor (TAFI) is a fibrinolytic inhibitor. Studies in coronary artery disease have reported increased TAFI activity (TAFI Act) and low TAFI antigen (TAFI Ag) levels. This controversy might be explained by the polymorphisms of its gene. Only the Thr325Ile polymorphism modulates both TAFI Ag and Act levels in vitro. This study assessed TAFI Ag and Act levels, TAFI Thr325Ile polymorphism, the fibrinolytic and protein C systems and some prothrombotic mutations in a young patient group (n = 127, aged < 51 years, with myocardial infarction) and a control group (n = 99) with similar characteristics. Patients exhibited hypofibrinolysis and higher plasminogen activator inhibitor-1 (PAI-1) levels. Although TAFI Ag was lower, TAFI Act level was significantly higher in patients and positively correlated with PAI-1, protein C inhibitor and the euglobulin lysis time. No differences between groups were found according to the Thr325Ile polymorphism. Irrespective of the genotype, patients had higher TAFI Act levels. The Ile-325 variant exhibited lower TAFI Ag levels. We suggest that the hypofibrinolysis observed in these patients results from an increase in both PAI-1 and TAFI Act, which is not related to the Thr325Ile polymorphism. Patients have high TAFI Act with low TAFI Ag levels, probably because of an increased stability of TAFI related to a fibrinolytic hypofunction.

Rheological behaviour of red blood cells in beta and deltabeta thalassemia trait.

In major and intermediate thalassemia a decrease in erythrocyte deformability and increased erythrocyte aggregability has been described, but few studies have dealt with the question of rheological red blood cell behaviour in minor beta and deltabeta thalassemia carriers, mostly in deltabeta, because it is a less common entity. To ascertain whether there are differences in red blood cell behaviour between minor thalassemia and controls and between both types of thalassemia trait beta and deltabeta, we determined erythrocyte deformability and aggregability in 30 beta and 30 deltabeta trait carriers diagnosed both with conventional methods and globin gene analysis, and in 40 age- and sex-matched controls. Erythrocyte deformability determined by means of the Rheodyn SSD showed a statistically significant lower Elongation Index (EI) at all the shear stresses tested in both thalassemic groups compared with controls (p<0.001). Minor beta thalassemia carriers showed lower EI than deltabeta carriers (p<0.001). Erythrocyte aggregability measured with the Myrenne aggregometer was significantly lower in both thalassemic groups than in controls (p<0.001), although no significant differences could be observed between both thalassemic groups. The rheological alterations found in thalassemia carriers are in part due to microcytosis, hypochromia and the morphological changes that characterize this kind of anaemia. The less altered deformability found in deltabeta carriers, is in agreement with the fact that it deals with a more benign trait.

Prothrombin G20210A mutation and oral contraceptive use increase upper-extremity deep vein thrombotic risk.

The role played by a hypercoagulable state, either inherited or acquired, in the pathogenesis of upper-extremity deep vein thrombosis (UEDVT) remains a question of debate. We performed a case-control study including 79 patients with a first objectively confirmed episode of UEDVT, 31 secondary and 48 primary, and 165 healthy controls. Nine patients (11.4%) with UEDVT were carriers of the prothrombin G20210A mutation vs. six (3.7%) in controls; P = 0.025, OR: 3.39 (95% CI 1.16 to 9.88). No statistical difference was observed between cases and controls for the factor V Leiden mutation, AT, protein C or protein S deficiency and anticardiolipin antibodies (ACAs). Thirteen (35.1%) UEDVT patients were oral contraceptive (OC) users vs. 12 (16%) controls; P = 0.020, OR: 2.89 (95% CI 1.16-7.21). When secondary UEDVT patients were compared with controls, no differences were observed in any of the risk factors analysed. On the other hand, when primary UEDVT was considered, six (12.5%) patients were carriers of the prothrombin G20210A mutation vs. six (3.7%) controls; P = 0.031, OR: 3.76 (95% CI 1.15-12.26). Regarding ACAs, a borderline statistical significance was observed when primary UEDVT was compared with controls, P = 0.048; OR: 4.88 (95% CI 1.05-22.61). In primary UEDVT, 52% of the fertile women were OC users vs. 16% of controls; P = 0.001, OR: 5.78 (95% CI 2.13-15.67). When the interaction of both factors, i.e. prothrombin G20210A mutation and OC intake, were considered, the risk increased markedly, indicating a synergistic effect as observed with other thrombotic locations. In patients with primary UEDVT screening for antithrombin, protein C and protein S deficiency and APC resistance would not be justified, although it might be reasonable to determine the carrier status of the prothrombin G20210A mutation only in OC users.

Erythrocyte deformability in survivors of acute myocardial infarction measured by two different methodologies.

In order to ascertain whether erythrocyte deformability (ED) is involved in chronic coronary syndromes, this rheological property was determined in 92 survivors of acute myocardial infarction (AMI) who had had the acute event 3 years ago and in 150 volunteers. From the 92 AMI survivors in 50 (43 males, 7 females aged 61+/-9 years) ED was determined with filtrometric techniques (Hanss Hemorheometre) and in 42 (32 males, 10 females aged 63+/-11 years) with laser diffractometric ones (Rheodyn SSD). The control group consisted of 66 and 84 volunteers whose ED was measured with the above mentioned devices respectively. Patients and controls were matched for age, sex, total cholesterol and triglyceride levels. With the Hanss Hemorheometre, the Rigidity Index (RI) was higher in patients than in controls (9.4+/-1.2 vs 8.7+/-1.5; p=0.01) although after adjusting for confounding variables (MCV and leukocyte count) in a logistic regression analysis the RI was no longer statistically significant. With the Rheodyn SSD the Erythrocyte Elongation Index (EEI) determined at 12, 30 and 60 Pa, did not show statistically significant differences between cases and controls at any of the shear stresses tested. Our results suggest that AMI survivors who had had the ischemic event 3 years ago do not show decrease RBC deformability with either of the two methodologies used. Red blood cell deformability does not appear to contribute to impaired microcirculatory blood flow in chronic coronary syndromes.

Quantitative real-time reverse transcription-PCR assay for urokinase plasminogen activator, plasminogen activator inhibitor type 1, and tissue metalloproteinase inhibitor type 1 gene expressions in primary breast cancer.

BACKGROUND: The plasminogen activation system and matrix metalloproteinases (MMPs) play a key role in the degradation of basement membrane and extracellular matrix in tissue remodeling, cancer cell invasion, and metastasis. METHODS: Quantitative real-time reverse-transcription-PCR (RT-PCR) assays were developed to quantify urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor type 1 (PAI-1), and tissue metalloproteinase inhibitor type 1 (TIMP-1) mRNA in 54 breast cancer tissues. Gene fragments were amplified in a LightCycler real-time PCR system using gene-specific primers and SYBR Green I. The results were normalized to beta-actin mRNA. We also quantified antigen and functional concentrations of these components. RESULTS: The intra- and interassay variabilities for mRNA quantification showed mean SDs for the crossing point of 0.12 and 0.15 cycles, respectively. PAI-1, uPA, and TIMP-1 mRNA and antigen concentrations and PAI-1 and uPA functional concentrations increased with tumor severity; the increase was statistically significant for PAI-1, uPA, and TIMP-1 mRNA and antigen concentrations and for uPA functional concentrations. Node-positive patients showed significantly higher PAI-1, uPA, and TIMP-1 mRNA and antigen concentrations than those who were node negative. CONCLUSIONS: Quantitative real-time RT-PCR is a highly sensitive, reproducible, and fast method for measuring gene expression of PAI-1, uPA, and TIMP-1 in breast cancer. These components may be involved in breast cancer development, and increased mRNA expression may be associated with a worse prognosis.

Experimental chronic interstitial pancreatitis induced by scorpion toxin in rats

Os efeitos do veneno de escorpiäo no trato gastrointestinal foram investigados no homem e em animais de experimentaçäo. O fluxo pancreático e o conteúdo enzimáticos säo aumentados por TsTX, o veneno purificado do escorpiäo Tityus serrulatus. Neste estudo, ratos machos receberam dose única intravenosa de TsTX. Eles foram sacrificados 20 dias após e o pâncreas foi removido. Estudos histopatológicos mostraram fibrose intersticial, infiltrado mononuclear, atrofia acinar e dilataçäo ductular. Também foram vistos, se bem que menos freqüentemente, infiltrado eosinofílico, hiperplasia ductular e densa secreçäo eosinofílica em ductos alargados. Todas as lesöes eram multifocais. Hiperplasia de ilhotas e nesidioblastose também foram observadas

Acute pancreatitis induced by scorpion toxin, tityustoxin: histopathological study in rats

A inoculaçäo experimental da toxina do escorpiäo Tityus serrulatus provoca pancreatite em cäes e ratos. O objetivo deste estudo é analisar a seqüência temporal de aparecimento das lesöes histopatológicas pancreáticas agudas, no rato, após a inoculaçäo do veneno. Ratos machos, adultos, da raça Wistar pesando 250 ñ 30 g, receberam injeçäo i.v. de tityustoxina (TsTX). Após tempos diversos de exposiçäo ao veneno (10, 20, 40 minutos e 24 e 96 horas) os animais foram sacrificados e o páncreas retirado, sendo, em seguida, submetido a exame histológico. Os resultados mostram aspectos seletivos de lesäo do pâncreas, produzida pela açäo de TsTX. Nos animais sacrificados após 10, 20 e 40 minutos da injeçäo do veneno, as lesöes foram do tipo degenerativo, com degranulaçäo e vacuolizaçäo. Após 24 e 96 horas de exposiçäo a toxina se estabelece o quadro característico de pancreatite aguda. Desde que o dano celular ao pâncreas é precocemente evidenciado, sugere-se uma açäo direta da toxina sobre este órgäo