脑卒中患者血浆凝血酶激活的纤溶抑制物的临床研究

目的研究总凝血酶激活的纤溶抑制物(TAFI)抗原(TAFI∶Ag)和活化的TAFI∶Ag(TAFIa∶Ag)与脑卒中的相关性,探讨二者在缺血性脑卒中(IS)和出血性脑卒中(ICH)的临床意义。方法采用酶联免疫吸附试验(ELISA)对228例脑卒中患者血浆TAFI水平变化进行研究分析,并将IS和ICH分别与对照组比较。结果与对照组[TAFI∶Ag(100.63±25.28)μg/mL;TAFIa∶Ag(126.43±31.88)ng/mL]相比,卒中发作时,2指标在IS[(118.72±31.41)μg/mL,(168.79±55.36)ng/mL]和ICH[(127.51±37.59)μg/mL,(207.99±73.71)ng/mL]均明显升高(P<0.01),并有较高发生率;TAFI评估脑卒中发病风险时,TAFIa∶Ag在IS是对照组的3倍,在ICH是对照组的7倍。结论血浆TAFI与脑卒中存在密切关系,TAFI升高大大地增加了脑卒中的发病风险。     

脑卒中患者血浆凝血酶激活的纤溶抑制物的临床研究

目的 研究总凝血酶激活的纤溶抑制物(TAFI)抗原(TAFI:Ag)和活化的TAFI:Ag(TAFIa:Ag)与脑卒中的相关性,探讨二者在缺血性脑卒中(IS)和出血性脑卒中(ICH)的临床意义.方法 采用酶联免疫吸附试验(ELISA)对228例脑卒中患者血浆TAFI水平变化进行研究分析,并将IS和ICH分别与对照组比较.结果 与对照组[TAH:AS(100.63±25.28)μg/mL;TAFIa:Ag(126.43±31.88)ns/mL]相比,卒中发作时,2指标在IS[(118.72±31.41)μg/mL,(168.79±55.36)ng/mL]和ICH[(127.51±37.59)μg/mL,(207.99±73.71)ng/mL]均明显升高(P＜0.01),并有较高发生率;TAH评估脑卒中发病风险时,TAFIa:Ag在Is是对照组的3倍,在ICH是对照组的7倍.结论 血浆TAH与脑卒中存在密切关系,TAFI升高大大地增加了脑卒中的发病风险.     

急性白血病纤溶系统检测的临床意义

目的探讨急性白血病(AL)患者纤溶系统的异常. 方法发色底物法和ELISA法测定93例患者血浆一系列纤溶指标. 结果患者血浆组织纤溶酶原激活物活性、D-二聚体(D-D)水平显著升高;纤溶酶原活性(PLG)、α2抗纤溶酶活性(α2-PI)、纤溶酶原激活抑制物活性(PAI)水平降低;缓解后均恢复正常. 结论 AL患者存在纤溶系统的激活,部分指标与AL分型、出血程度和预后有关.     

2型糖尿病患者血浆凝血酶激活的纤溶抑制物变化观察

目的评价血浆凝血酶激活的纤溶抑制物(TAFI)在2型糖尿病患者凝血及纤溶功能变化中的作用。方法检测90例2型糖尿病患者和30例与患者年龄相匹配的健康者血浆中TAFI、组织纤溶酶原激活物(t-PA)、纤溶酶原激活物抑制物(PAI-1)。结果TAFI的活性在2型糖尿病各组患者血浆中高于对照组(P<0.05),高蛋白尿组较尿蛋白正常组和低蛋白尿组升高(P<0.05)。t-PA在无并发症组低于对照组,但无统计学意义(P>0.05),高蛋白尿约较尿蛋白正常组和低蛋白尿组低(P<0.05)。PAI-1在2型糖尿病各组患者高于对照组(P<0.05),高蛋白尿组较尿蛋白正常组利低蛋白尿组升高(P<0.05)。TAFI的活性与t-PA和PAI-1含量有较好的相关性。结论检测2型糖尿病患者血浆中TAFI活性水平,对于预测2型糖尿病患者的微血管病变程度,防治2型糖尿病并发症有着重要意义。     

急性冠状动脉综合征合并糖尿病患者纤溶系统及血小板功能的研究——附68例报告

目的探讨ACS合并2型糖尿病患者纤溶系统及血小板最大聚集率的变化.方法256例ACS患者,根据其是否合并2型糖尿病分为糖尿病组(68例)及非糖尿病组(188例),并将100名同期在本院行体检的正常志愿者设为对照组.测定所有人员的组织型纤溶酶原激活物、纤溶酶原激活物抑制物-1含量及血小板最大聚集率,比较组间差异.结果糖尿病组血浆组织型纤溶酶原激活物含量[(5.5±1.7)μg/L]较非糖尿病组[(8.8±1.5)μg/L]低,而两组均较对照组[(9.7±2.8)μg/L]低(P＜0.01～P＜0.05).糖尿病组纤溶酶原激活物抑制物-1含量[(45±3)μg/L]较非糖尿病组[(35±3)μg/L]高,而两组均较对照组[(17±7)μg/L]高(P＜0.01～P＜0.05).糖尿病组血小板最大聚集率[(78±14)%]明显高于非糖尿病组[(66±11)%],而两组均较对照组[(56±14)%]高(P＜0.01～P＜0.05).结论ACS合并2型糖尿病患者与单纯ACS患者比较,其纤溶系统异常更明显,血小板凝聚性更强,提示此类患者应加强抗凝及抗血小板治疗.     

高血压病患者血浆PAI-1、t-PA及t-PA/PAI-1水平的变化

目的通过对原发性高血压患者血浆纤溶酶原活化物抑制剂1(PAI-1)、组织型纤溶酶原活化物(t-PA)含量及t-PA/PAI-1比值的测定,了解高血压患者纤溶功能的情况。方法未用药物干预过的轻至中度原发性高血压患者(高血压组)64例,正常对照组42例,采用酶联免疫吸附双抗体夹心法测定两组血浆PAI-1、t-PA含量并计算t-PA/PAI-1。结果正常组PAI-1含量明显低于高血压组,(13.5±5.0)μg/L vs(53.0±22.6)μg/L(P<0.01);正常组t-PA/PAI-1明显高于高血压组,(0.83±0.52)μg/L vs(0.25±0.13)μg/L(P<0.01)。结论高血压患者的纤溶功能减退。     

冠心病患者血浆凝血酶激活的纤溶抑制物的检测及其临床意义

目的　检测正常人群血浆中 TAFI:Ag和 TAFI:A的水平 ,确立正常人血浆中 TAFI:Ag和TAFI:A的参考值范围及其在冠心病患者血浆中的变化。方法　应用 ELISA方法测定 34名正常人、1 9例冠心病患者及 1 5例 DIC患者血浆中 TAFI:Ag的含量 ,应用发色底物法检测血浆中 TAFI:A的水平。对正常人、冠心病患者血浆中 TAFI:Ag和 TAFI:A的含量进行对照分析。结果　正常人 TAFI:Ag平均值为 ( 77± 2 8) % ,参考值范围为 2 1 %～ 1 33% ,TAFI:A平均值为 ( 2 4± 5 ) μg/ml,参考值为 1 4～ 34μg/ml。冠心病患者血浆中 TAFI:Ag为 ( 1 5 6± 32 ) % ,TAFI:A为 ( 4 3± 7) μg/ml。结论　正常人血浆中的TAFI:Ag含量具有很大变异性 ,正常人 TAFI的活性与 TAFI抗原含量呈剂量相关性 ,冠心病患者血浆中 TAFI:Ag和 TAFI:A显著增高 ,表明 TAFI在冠心病发病中起一定作用。     

阻塞性睡眠呼吸暂停低通气综合征患者血管内皮细胞及纤溶系统功能变化

目的：探讨阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者血管内皮细胞及纤溶系统功能变化。方法：根据多导睡眠呼吸监测仪监测结果，选择年龄、性别、体重指数(BMI)无明显差异的OSAHS患者52例和健康者48例。以Clauss法测定纤维蛋白原(Fg)，以发色底物法测定组织纤溶酶原激活物活性(tPA：A)、纤溶酶原激活物抑制物-1活性(PAI-1：A)，以酶联免疫法测von Willebrand因子含量(vWF)、组织纤溶酶原激活物含量(tPA：Ag)、纤溶酶原含量(PLg：Ag)和纤溶酶原激活物抑制物-1含量(PAI-1：Ag)。结果：与对照组比较，(3SAHS组vWF、Fg、PAI-1：A、PAI-1：Ag水平明显升高，PLg：Ag、tPA：Ag含量明显降低，tPA：A无明显变化。结论：OSAHS患者血管内皮细胞功能受损，纤溶系统功能降低。     

血浆PAI-1和TAFI的变化对STEMI患者静脉溶栓治疗后血管再通的预测价值

目的 通过检测急性心肌梗死( AMI)患者静脉溶栓前、后2小时内血浆凝血酶激活的纤溶抑制物(TAFI)和纤溶酶原激活物抑制剂-1(PAI-1)的含量,探讨两者的变化是否对溶栓后血管再通具有预测价值.方法2007年1月至2009年3月期间收集广州医学院第二附属医院急诊科16例急性ST段抬高心肌梗死(STEMI)患者溶栓前、后0.5,1,1.5,2h的血浆标本,并以16名健康人作为健康对照组,用ELISA法测定血浆中TAFI和PAI-1的含量.结果 (1)与健康对照组相比,STEMI患者溶栓前的血浆PAI-1水平显著升高(P＜0.01);而TAFI活性与对照组相比差异无统计学意义.(2)与溶栓前相比,溶栓后0.5,1,1.5,2h的血浆TAFI活性较溶栓前比较,差异无统计学意义(P＞0.05);溶栓后1.5,2h的血浆PAI-1显著升高(P＜0.01).(3)溶栓后2h冠脉未通组PAI-1水平显著高于再通组(P＜0.05);而冠脉未通组和再通组TAFI活性差异无统计学意义(P＞0.05).结论 升高的血浆PAI-1在溶栓后2h下降可能对溶栓后血管再通具预测价值,TAFI对血管冉通不具预测价值.     

凝血酶激活的纤溶抑制物与深静脉血栓形成相关分析

目的：探讨凝血酶激活的纤溶抑制物（TAFI）与深静脉血栓（DVT）形成的关系。方法：应用发色底物法和ELISA法分别测定了30例DVT患者和30例正常对照者TAFI的活性及抗原。结果：DVT组TAFI的活性及抗原[TFAIAct（58.69±15.24）μg/ml,TAFI Ag（123.45±25.64）%]均较对照组[TAFI Act（30.15±9.36）μg/ml,TAFI Ag（69.35±24.13）%]显著增高（P〈0.01）。结论：TAFI具有抑制纤溶的作用,可能与DVT形成有关。     

Does an enzyme other than thrombin contribute to unexpected changes in the levels of the different forms of thrombin activatable fibrinolysis inhibitor in patients with hemophilia A, hemophilia B and von Willebrand disease?

Pro-thrombin activatable fibrinolysis inhibitor (pro-TAFI), also called plasma procarboxypeptidase B or U, is one of the modulators of fibrinolysis in blood. Pro-TAFI is activated by thrombin/thrombomodulin complex or by plasmin to a carboxypeptidase B-like enzyme (TAFI) of 35.8 kD molecular weight. TAFI spontaneously becomes inactive as a result of a temperature-dependent conformational change in the protein (TAFIi). In this study, pro-TAFI, total TAFI antigen and TAFI-TAFIi antigen levels were measured in 32 patients with hemophilia A, 4 patients with hemophilia B, 21 patients with von Willebrand disease (VWD) and 13 healthy controls. A statistically significant decrease in pro-TAFI was found in all groups (10.72+/-4.57 mg/L (p<0.001); 8.00+/-2.35 mg/L (p<0.01) and 8.98+/-2.33 mg/L (p <0.001) for hemophilia A, hemophilia B and VWD, respectively) compared to controls (17.85+4.61 mg/L). A statistically significant increase in TAFI-TAFIi antigen was found in hemophilia A (1.05+/-1.01 mg/L) (p<0.05) and in VWD patients (0.96+/-1.01 mg/L) (p<0.05) compared to controls (0.55+/-0.36 mg/L). There was no difference in total TAFI antigen levels between any group of patients and the controls. Neither did pro-TAFI nor TAFI-TAFIi levels differ within the group of hemophilia A patients in relation to severity (mild, moderate and severe) or among the VWD patients in relation to subtype (type 1, type 2A and type 3). These findings indicate an increased conversion of pro-TAFI to TAFI and/or TAFIi in patients with bleeding disorders. As thrombin generation is seriously impaired in these patients and almost absent in hemophilia A and B and in type 3 VWD, it is possible that plasmin mediates pro-TAFI activation in these patients. Enhanced fibrinolysis via generation of plasmin has previously been reported in hemophilia and VWD. Activation of pro-TAFI by plasmin may be a feedback mechanism that counterbalances increased fibrinolysis in patients with bleeding disorders. The relationship between the TAFI activation pathway and bleeding complications associated with hemophilia A, hemophilia B and VWD requires further investigation.     

Metabolic syndrome accompanied by hypercholesterolemia is strongly associated with proinflammatory state and impairment of fibrinolysis in patients with type 2 diabetes: synergistic effects of plasminogen activator inhibitor-1 and thrombin-activatable fibrinolysis inhibitor

OBJECTIVE: To determine whether plasma concentrations of thrombin-activatable fibrinolysis inhibitor (TAFI) in patients with type 2 diabetes were associated with components of metabolic syndrome (MS), including high-sensitivity C-reactive protein (hs-CRP), plasminogen activator inhibitor (PAI)-1, and LDL cholesterol. RESEARCH DESIGN AND METHODS: We studied 136 consecutive patients with type 2 diabetes. Diagnosis of MS was diagnosed by current criteria. Hypercholesterolemia (HC) was defined as serum LDL cholesterol >140 mg/dl (3.6 mmol/l) or treatment with a statin. For comparisons, diabetic patients were divided into four groups: those with no MS and no HC (n = 38), with MS but not HC (n = 39), with no MS but with HC (n = 26), and with both MS and HC (n = 33). RESULTS: Considering all patients with type 2 diabetes, plasma PAI-1 was strongly associated with MS components such as BMI, triglyceride, alanine aminotransferase, a homeostasis model assessment of insulin resistance, and hs-CRP. Plasma TAFI only correlated positively and independently with LDL cholesterol. Plasma concentrations of plasmin-alpha2-antiplasmin complex (PAP), a measure of fibrinolytic activity in blood, showed a significant negative correlation with plasma PAI-1 but not TAFI. Diabetic patients with both MS and HC had the highest serum hs-CRP concentrations and the lowest plasma PAP concentrations. CONCLUSIONS: LDL cholesterol is a main determinant of plasma TAFI in patients with type 2 diabetes. Coexistence of MS and HC synergistically accelerates inflammation and impairment of fibrinolysis via elevated concentrations of both TAFI and PAI-1, which inhibit fibrinolysis.     

Enhancement of fibrinolysis by EF6265 [(S)-7-amino-2-[[[(R)-2-methyl-1-(3-phenylpropanoylamino)propyl]hydroxyphosphinoyl] methyl]heptanoic acid], a specific inhibitor of plasma carboxypeptidase B

Plasma procarboxypeptidase B, also known as thrombin-activatable fibrinolysis inhibitor (TAFI), is converted by thrombin into the active enzyme, carboxypeptidase B (CPB)/activated TAFI. Plasma CPB down-regulates fibrinolysis by removing carboxy-terminal lysines, the ligands for plasminogen and tissue-type plasminogen activator (tPA), from partially degraded fibrin. To target thrombosis in a new way, we have identified and optimized a phosphinic acid-containing inhibitor of CPB, EF6265 [(S)-7-amino-2-[[[(R)-2-methyl-1-(3-phenylpropanoylamino) propyl]hydroxyphosphinoyl]methyl]heptanoic acid] and determined both the pharmacological profile and pathophysiological role of CPB in rat thrombolysis. EF6265 specifically inhibited plasma CPB activity with an IC(50) (50% inhibitory concentration) of 8.3 nM and enhanced tPA-mediated clot lysis in a concentration-dependent manner. EF6265 decreased detectable thrombi (percentage of glomerular fibrin deposition; control, 98 +/- 1.1; EF6265, 0.1 mg/kg, 27 +/- 9.1) that had been generated by tissue factor in a rat microthrombosis model with concomitant increases in plasma D-dimer concentration (control, <0.5 microg/ml; EF6265, 0.1 mg/kg, 15 +/- 3.5 microg/ml). EF6265 reduced plasma alpha2-antiplasmin activity to a lesser extent than tPA. In an arteriovenous shunt model, EF6265 (1 mg/kg) enhanced exogenous tPA-mediated thrombolysis under the same conditions that neither EF6265 nor tPA (600 kIU/kg) alone reduced thrombi. EF6265 (1 and 30 mg/kg) did not affect the bleeding time in rats. Moreover, it did not prolong the bleeding time evoked by tPA (600 kIU/kg). These results confirm that circulating procarboxypeptidase B functions as a fibrinolysis inhibitor's zymogen and validates the use of CPB inhibitors as both an enhancer of physiological fibrinolysis in microcirculation and as a novel adjunctive agent to tPA for thromboembolic diseases while maintaining a small effect on primary hemostasis.     

急性白血病患者止血功能检测的临床意义

目的：探讨急性白血病（ＡＬ）患的止血功能及其与出血症状及预后的关系。方法采用ＥＬＩＳＡ或发色底物法对９３例ＡＬ患浆凝血、抗凝和纤溶指标进行了检测。结果治疗前血浆Ｐ－选择素、可溶性纤维蛋白单体复合物（ＳＦＭＣ）、凝血酶调节蛋白（ＴＭ）、组织型纤溶酶原激活剂、Ｄ－二聚体（Ｄ－Ｄ）水平显升高;高白Ｃ抗原（ＰＣ：Ａｇ）、纤溶酶原活性（ＰＬＧ）、α２抗纤溶酶（α２－ＰＩ）、纤溶酶原激活剂抑制物（ＰＡ）     

Activation of the fibrinolytic system and utilization of the coagulation inhibitors in sepsis: comparison with severe sepsis and septic shock

OBJECTIVES: To determine whether the fibrinolytic system is activated and coagulation inhibitors are utilized in sepsis, to compare the findings detected in sepsis with those found in severe sepsis and septic shock, and to compare the role played by different infectious pathogens on fibrinolysis and coagulation inhibitors. DESIGN AND SETTING: Prospective study comparing patients with sepsis, severe sepsis, and septic shock and healthy volunteers in the general intensive care unit of a tertiary university hospital. PATIENTS: Eighty-two consecutive septic patients (47 with sepsis, 18 with severe sepsis, and 17 with septic shock), and 14 healthy volunteers (controls). MEASUREMENTS AND RESULTS: After blood sampling we measured activation markers of fibrinolysis [plasmin/alpha(2)-antiplasmin complexes (PAP), complexes of tissue plasminogen activator/plasminogen activator inhibitor (tPA/PAI), fibrin(ogen) degradation products (FDPs), D-dimmers fibrin degradation products (D-d)], the utilization marker of antithrombin III (ATIII) thrombin/antithrombin complexes (TAT), several factors of fibrinolysis [plasminogen, tissue plasminogen activator (tPA), plasminogen activator inhibitor 1 (PAI-1), alpha(2)-antiplasmin], and the natural coagulation inhibitors [ATIII, protein C (PrC), protein S (PrS)]. In sepsis, PAP, FDPs, D-d, and TAT were increased to 439.8+/-32.35 microg/l, 57% positive, 49% positive, and 3.46+/-0.27 microg/l, respectively, compared with control subjects (205.57+/-28.58 microg/l, 0% positive, 7% positive, and 1.61+/-0.1 microg/l, respectively). These markers further increased in severe sepsis and septic shock. With the exception of a decrease in ATIII and an increase in tPA and PAI-1, coagulation inhibitors and factors of fibrinolysis were not changed in sepsis. In severe sepsis and mainly in septic shock, coagulation inhibitors (ATIII, PrC) and plasminogen were markedly decreased, whereas tPA and PAI-1 were further increased. All changes were independent of the causative infectious pathogen. CONCLUSIONS: Fibrinolysis is strongly activated and ATIII is utilized in sepsis. These findings are further enhanced in severe sepsis and septic shock. In sepsis only ATIII is decreased. In contrast, in severe sepsis and mainly in septic shock plasminogen and the main coagulation inhibitors (i.e., ATIII, PrC) are depleted, indicating exhaustion of fibrinolysis and coagulation inhibitors. Finally, Gram-positive, Gram-negative and other micro-organisms produce identical impairment.     

Evaluation of PAI-039 [{1-benzyl-5-[4-(trifluoromethoxy)phenyl]-1H-indol-3-yl}(oxo)acetic acid], a novel plasminogen activator inhibitor-1 inhibitor, in a canine model of coronary artery thrombosis

We tested a novel, orally active inhibitor of plasminogen activator inhibitor-1 (PAI-1) in a canine model of electrolytic injury. Dogs received by oral gavage either vehicle (control) or the PAI-1 inhibitor PAI-039 [{1-benzyl-5-[4-(trifluoromethoxy)phenyl]-1H-indol-3-yl}(oxo)acetic acid] (1, 3, and 10 mg/kg) and were subjected to electrolytic injury of the coronary artery. PAI-039 caused prolongation in time to coronary occlusion (control, 31.7 +/- 6.3 min; 3 mg/kg PAI-039, 66.0 +/- 6.4 min; 10 mg/kg, 56.7 +/- 7.4 min; n = 5-6; p < 0.05) and a reduced thrombus weight (control, 7.6 +/- 1.5 mg; 10 mg/kg PAI-039, 3.6 +/- 1.0 mg; p < 0.05). Although occlusive thrombosis was observed across all groups based upon the absence of measurable blood flow, a high incidence (>60%) of spontaneous reperfusion occurred only in those groups receiving PAI-039. Spontaneous reperfusion in the 10 mg/kg PAI-039 group accounted for total blood flow (area under the curve of coronary blood flow) of 99.6 +/- 11.7 ml after initial thrombotic occlusion (p < 0.05 compared with control). Plasma PAI-1 activity was reduced in all drug-treated groups (percentage of reduction in activity p < 0.05; 10 mg/kg PAI-039), whereas ADP-, 9,11-dideoxy-11alpha,9alpha-epoxymethanoprostaglandin F(2alpha) (U46619)-, and collagen-induced platelet aggregation, as well as template bleeding and prothrombin time, remained unaffected by PAI-039. Ex vivo clot lysis analysis revealed normal clot formation but accelerated clot lysis in PAI-039-treated groups. The pharmacokinetic profile of PAI-039 indicated an oral bioavailability of 43 +/- 15.3% and a plasma half-life of 6.2 +/- 1.3 h. In conclusion, PAI-039 is an orally active prothrombolytic drug that inhibits PAI-1 and accelerates fibrinolysis while maintaining normal coagulation in a model of coronary occlusion.     

Plasma proteinase inhibitor activity and hemostasis tests in children with nephrotic syndrome. Effect of prednisone alone and prednisone plus epsilon-aminocaproic acid treatment regimens: a preliminary report

Neutrophil-derived proteinases cause glomerular injury by proteolysis of the glomerular basement membrane and alterations in glomerular metabolism. Recently, a marked elevation of the plasma elastase complex with alpha1-proteinase inhibitor (alpha 1-PI) both in the acute phase and during remission of nephrotic syndrome (NS) compared with age-matched controls was reported. In experimental immune-mediated glomerulonephritis epsilon-aminocaproic acid (EACA) significantly reduced albuminuria, and it was suggested that this may be linked with the antiproteolytic activity of the drug. We studied plasma antithrombin III (AT-III), alpha 1-PI, alpha 2-antiplasmin (alpha 2-A), alpha 2-macroglobulin (alpha 2-M) activity, and some blood coagulation and fibrinolysis tests in children with frequently relapsing prednisone-responsive NS. Also, the effect of prednisone alone (Group I, n = 9) and prednisone plus EACA (Group II, n = 10) treatment regimens on the studied parameters was estimated. All investigations were performed on admission to the hospital and after approximately 13 days of prednisone alone therapy (Group I), as well as before the administration of prednisone plus EACA and 24 hours after the last dose of EACA, ie, after approximately 5 days of treatment (Group II). Prednisone was administered at the usual dose of approximately 2 mg/kg/d and EACA was given orally at the doses of 72 to 230 mg/kg of body weight per day for 3 to 10 days. In the acute phase of disease, NS patients (n = 19) were shown to have a statistically significant decrease of plasma AT-III (16.4 +/- 4.7 vs. 21.9 +/- 2.5 IU/mL) and alpha 1-PI (1.28 +/- 0.6 vs. 1.97 +/- 0.34 IU/mL) activity, as well as a marked increase in plasma alpha 2-M activity (14.96 +/- 5.81 vs. 9.6 +/- 1.6 IU/mL), and fibrinogen concentration (5.51 +/- 1.78 vs. 2.96 +/- 0.34 g/L) compared to the age-matched controls; no significant changes in plasma alpha 2-A activity, plasminogen concentration, euglobulin clot lysis time, activated partial thromboplastin time (APTT), or thromboplastin time were noted. In children treated with prednisone alone, a marked increase in plasma AT-III (by 76%, P < 0.001) and alpha 2-A (36%, P < 0.019) activity, and a significant decrease of the plasma fibrinogen concentration (6.07 +/- 1.66 vs. 3.17 +/- 1.64 g/L, P < 0.001), and APTT (45.1 +/- 7.6 vs. 33.8 +/- 4.4 s, P < 0.001) were found. Prednisone plus EACA therapy resulted in a significant increase in plasma AT-III activity (by 53%, P < 0.003), whereas plasma fibrinogen concentration and APTT remained unchanged. However, statistically significant differences between the pre- and posttreatment plasma AT-III, alpha 1-PI, and alpha 2-A activities in these patients were observed. There was also a relationship between EACA dose and the percentage change in plasma alpha 2-A activity. In a few patients receiving prednisone plus EACA regimen, side effects that included purulent rhinitis, pharyngitis, increases in body temperature, loose stools, and an approximately 20% to 30% decrease in systolic and diastolic arterial blood pressure were observed. Thus, although the prednisone plus EACA treatment regimen seems to offer new therapeutic possibilities in some patients with NS, it should not be used in acute phase of the disease.     

Development of sandwich-type ELISAs for the quantification of rat and murine thrombin activatable fibrinolysis inhibitor in plasma.

BACKGROUND: Altered plasma levels of thrombin activatable fibrinolysis inhibitor (TAFI) are associated with a large number of pathologies. Rat and murine models are frequently used to study the pathophysiological role of TAFI in vivo but immunological tools to quantify rat and murine TAFI are lacking. OBJECTIVE: The production of monoclonal antibodies (mAb) towards rat TAFI and the development of an ELISA for the quantification of rat and murine TAFI in plasma. METHODS AND RESULTS: Monoclonal antibodies were raised in TAFI-deficient mice towards (activated) recombinant rat TAFI. Pair-wise testing of the mAb revealed three suitable ELISA combinations, namely RT36A3F5/RT30D8-HRP, RT36A3F5/RT82F12-HRP and RT82F12/RT36A3F5-HRP. All three ELISAs are highly specific for rat and murine TAFI. TAFI concentrations in the lower ng mL(-1) range can be determined in plasma samples with a high reproducibility. Comparing TAFI antigen levels measured by these ELISAs with TAFIa activity values determined by activity based assays revealed excellent correlations (R(2) > 0.98). The average antigen levels of 20 individual rat plasma samples were 16 +/- 2 microg mL(-1) using the RT36A3F5-RT30D8-HRP, 12 +/- 2 microg mL(-1) using the RT36A3F5-RT82F12-HRP and 21 +/- 2 microg mL(-1) using the RT82F12-RT36A3F5-HRP ELISA. The determined antigen levels in rat plasma are similar to the levels reported for human plasma. CONCLUSIONS: We developed three highly specific and extremely sensitive sandwich-type ELISAs for the quantification of rat and murine TAFI in plasma. The described ELISAs will facilitate in vivo investigation on the pathophysiological role of TAFI.     

Congenital Deficiency of α2-Plasmin Inhibitor Associated with Severe Hemorrhagic Tendency

alpha(2)-Plasmin inhibitor (alpha(2)PI) is a recently characterized, fast-reacting plasmin inhibitor in human plasma that appears to play an important role in regulation of in vivo fibrinolysis. We report here a case of complete deficiency of alpha(2)PI in man. The patient, a 25-yr-old Japanese man, had a life-long severe bleeding tendency (hemarthrosis and excessive bleeding after trauma). The following tests were within normal limits: platelet count, bleeding time, thrombin time, prothrombin time, partial thromboplastin time, titers of known clotting factors, platelet glass bead retention, Factor VIII-related antigen, platelet aggregation by ADP, collagen and ristocetin, and clot retraction. Routine liver function tests were also normal. The only abnormal finding was that whole blood clot lysis was extemely rapid and was complete in 4-8 h. The concentration of plasma protease inhibitors, including alpha(2)-macro-globulin, antithrombin III, alpha(1)-antitrypsin, and C1INH, were all normal. The concentration of alpha(2)-PI in the patient's plasma, assayed by immunological methods, was <0.1 mg/100 ml (normal concentration, 6.1+/-0.88 mg/100 ml [mean+/-SE]) and functional assays showed a complete deficiency of alpha(2)PI. Addition of purified alpha(2)PI to the patient's whole blood completely corrected the accelerated fibrinolysis. The patient's parents, four siblings, and four other members of this family were asymptomatic, but the titers of alpha(2)PI in their plasmas were congruent with50% of normal pooled plasma. There were three consanguineous marriages in this family, and the alpha(2)PI deficiency appears to have been inherited as an autosomal recessive trait. We speculate that alpha(2)PI deficiency in this patient has led to uninhibited in vivo fibrinolysis that probably causes the severe hemorrhagic tendency. Thus, this study indicates the important role of alpha(2)PI in hemostasis.