腔隙性脑梗死患者血浆组织因子和组织因子途径抑制物抗原水平的测定

目的探讨腔隙性脑梗死(lacunarinfarct,LI)患者血浆组织因子(tissue factor,TF)和组织因子途径抑制物(tissuefactor pathwayinhibitor,TFPI)测定的临床意义以及组织因子途径在LI发病中的作用.方法择确诊的LI患者63例,采用酶联免疫吸附的方法测定血浆TF和TFPI相关指标抗原水平,与正常对照组比较并对不同危险因素患者组之间的结果进行分析.结果①与正常对照组比较,LI患者组血浆TF抗原水平显著增高(217.4±101.3pg/ml对140.9±27.1pg/ml,P=0.0003)、游离TFPI抗原水平降低(41.4±16.7 ng/ml对30.0±18.6 ng/ml,P=0.005);②合并高血压、糖尿病和血脂异常LI患者血浆TFPI相关指标的改变不同;③LI患者血浆t-TFPI和tr-TFPI抗原水平与血浆TF抗原水平相关.结论LI患者血浆组织因子途径改变表现为凝血活性增高和抗凝活性减低.     

Poor anticoagulant response to tissue factor pathway inhibitor in patients with venous thrombosis

Summary.  Tissue factor pathway inhibitor (TFPI) is of major importance in regulating the coagulation triggering effects of tissue factor. An association between TFPI deficiency and thrombosis has still not been clearly demonstrated. We evaluated the anticoagulant activity of exogenous TFPI added either to the plasma of patients with venous thrombosis ( n  = 118) or to the plasma of healthy controls similar in terms of mean age and sex ratio ( n  = 107). A poor anticoagulant response to TFPI, defined as TFPI resistance, was observed in 4.7% of controls and in 11.0% of patients. TFPI resistance was associated with an almost threefold increase in the risk of thrombosis and could therefore represent a novel hemostatic risk factor for venous thrombosis.     

心肺复苏后组织因子和组织因子途径抑制物的动态变化和临床意义

目的 观察院内心肺复苏后不同时间点组织因子(TF)和组织因子途径抑制物(TFPI)水平的动态变化特点并探讨其临床意义.方法 选择2005年9月至2007年9月温州医学院附属第一医院急诊科收治的年龄>16岁明确心搏停止时间的心肺复苏患者24例,依据是否达到自主循环恢复标准随机分为ROSC和末ROSC两组,分别记录小同患者心搏停止的病因和临床特点,并用ELISA方法 检测心肺复苏(CPR)后30 min,60 min,6 h,24 h,48 h血清TF和TFPI抗原浓度,10例来自健康体检的健康自愿者为对照组.计量数据用均数±标准差((-x)±s)来表示,两组计量数据的比较采用独立样本t检验,三组及以上计量数据比较采用单因素方差分析法,计数数据的比较采用旧格表精确x2榆验,以P<0.05为差异具有统计学意义.结果 与对照组比较,ROSC组患者在CPR 30 min血TF水平显著升高(P<0.01),在CPR 6 h达高峰,在CPR48 h时已下降;与对照组及ROSC组同时点比较,末ROSC组血TF水平更是显著升高(P<0.01).与对照组比较,在CPR后30 min,ROSC和未ROSC两组血清TFPI水平差异无统计学意义(P>0.05),60 min后ROSC组血清TFPI水平逐渐升高并有显著差别(P<0.01或<0.05).与对照组比较,未ROSC组和ROSC组患者在CPR 30 min时的TF/TFPI水平均显著性升高(P<0.01),且前者显著高于后者(P<0.01),在ROSC组IF/TFPI值在CPR后6 h有显著升高(P<0.01),在48 h下降.结论 血清TF和TFPI水平在院内心肺复苏的患者中明显升高,CPR后半小时的TF和TF/TFPI的水平可用于判断预后.     

Pro- and non-coagulant forms of non-cell-bound tissue factor in vivo

Summary.  Background : Concentrations of non-cell-bound (NCB; soluble) tissue factor (TF) are elevated in blood collecting in the pericardial cavity of patients during cardiopulmonary bypass (CPB). Previously, we reported microparticles supporting thrombin generation in such blood samples. In this study we investigated the extent of microparticle association of the NCB form of TF in pericardial and systemic blood, and whether this microparticle-associated form is active in thrombin generation compared with non-microparticle-bound, (fluid-phase) TF. Methods : Systemic and pericardial blood samples were collected before and during CPB from six patients undergoing cardiac surgery. Microparticles were isolated by differential centrifugation and their thrombin-generating capacity measured in a chromogenic assay. Microparticle-associated and fluid-phase forms of NCB TF were measured by ELISA. Microparticle-associated TF was visualized by flow cytometry. Results : In pericardial samples, 45–77% of NCB TF was microparticle-associated, and triggered factor VII (FVII)-mediated thrombin generation in vitro . Microparticles from systemic samples triggered thrombin generation independently of FVII, except at the end of bypass ( P  = 0.003). The fluid-phase form of TF did not initiate thrombin generation. Both forms of NCB TF were, at least in part, antigenically cryptic. Conclusions : We demonstrate the occurrence of two forms of NCB TF. One form, which is microparticle-associated, supports thrombin generation via FVII. The other form, which is fluid-phase, does not stimulate thrombin formation. We hypothesize that the microparticle-associated form of NCB TF may be actively involved in postoperative thromboembolic processes when pericardial blood is returned into the patients.     

子痫前期患者组织因子、组织因子途径抑制物与血清可溶性血管内皮生长因子受体1的相关性

目的探讨子痫前期患者外周血组织因子(TF)、组织因子途径抑制物(TFPI)与及可溶性血管内皮生长因子受体1(s Flt-1)水平的相关性。方法酶联免疫吸附试验(ELISA)检测健康孕妇、非重度子痫前期孕妇、重度子痫前期孕妇血浆TF、TFPI水平以及血清s Flt-1水平;免疫组化检测各组胎盘TF抗原的表达。结果 3组患者血浆及胎盘TF、血清s Flt-1水平均有显著差异,且随病变程度的增加逐渐升高。3组TF/TFPI比值有显著差异,随病变程度的增加亦逐渐升高。与非重度PE组相比,重度PE组血清s Flt-1水平显著升高(P0.05)。在子痫前期患者中,血浆TF、TF/TFPI比值与血清s Flt-1水平呈正相关。3组中胎盘TF表达与血清s Flt-1水平无相关性。在TF165.9 pg/m L组中,血浆、胎盘TF、血浆TFPI与血清s Flt-1水平呈正相关。结论子痫前期患者血浆TF、TF/TFPI比值与血清s Flt-1水平存在正相关关系。     

Temporal expression of alternatively spliced forms of tissue factor pathway inhibitor in mice

Summary.  Background: Mouse tissue factor pathway inhibitor (TFPI) is produced in three alternatively spliced isoforms that differ in domain structure and mechanism for cell surface binding. Tissue expression of TFPI isoforms in mice was characterized as an initial step for identification of their physiological functions. Methods and Results: Sequence homology demonstrates that TFPIα existed over 430 Ma while TFPIβ and TFPIγ evolved more recently. In situ hybridization studies of heart and lung did not reveal any cells exclusively expressing a single isoform. Although our previous studies have demonstrated that TFPIα mRNA is more prevalent than TFPIβ or TFPIγ mRNA in mouse tissues, western blot studies demonstrated that TFPIβ is the primary protein isoform produced in adult tissues, while TFPIα is expressed during embryonic development and in placenta. Consistent with TFPIβ as the primary isoform produced within adult vascular beds, the TFPI isoform in mouse plasma migrates like TFPIβ in SDS-PAGE and mice have a much smaller heparin-releasable pool of plasma TFPIα than humans. Conclusions: The data demonstrate that alternatively spliced isoforms of TFPI are temporally expressed in mouse tissues at the level of protein production. TFPIα and TFPIβ are produced in embryonic tissues and in placenta while adult tissues produce almost exclusively TFPIβ.     

Effect of long-term hormone replacement therapy on tissue factor pathway inhibitor and thrombin activatable fibrinolysis inhibitor in healthy postmenopausal women: a randomized controlled study

Summary.  It was recently reported from the Women's Health Initiative that healthy women using combined hormone replacement therapy (HRT) for 5 years have an increased cardiovascular risk. We hypothesize that the increased risk is confined to subgroups of atherosclerotic women. Such women may have higher arterial tissue factor expression and higher thrombin formation, and changes in tissue factor pathway coagulation inhibitor (TFPI) and thrombin activatable fibrinolysis inhibitor (TAFI) may be deleterious. Healthy postmenopausal women ( n  = 719) were randomized to hormone therapy [ n  = 357; opposed ( n  = 290) and unopposed ( n  = 67)] or no treatment ( n  = 362). Plasma TFPI and TAFI and the TFPI −287T/C and TAFI −438G/A polymorphisms were measured 5–6 years after randomization. Concentrations of TFPI were significantly lower in the hormone group than in the control group ( P  < 0.001) and in all genotypes of the TFPI polymorphism. Overall, concentrations of TAFI did not differ between the two groups but were reduced by hormone therapy in homozygotes for the rare TAFI −438 A allele ( P  < 0.05). The hormone effects on TFPI and TAFI were similar in smokers and non-smokers and in women using unopposed and opposed therapy. The observed decrease in TFPI may contribute to the increased cardiovascular risk associated with HRT.     

High titers of autoantibodies to tissue factor pathway inhibitor are associated with the antiphospholipid syndrome

Summary.  As the activity of the tissue factor pathway inhibitor (TFPI) may be impaired in patients with antiphospholipid antibodies (aPL), 162 aPL patients were evaluated for autoantibodies to recombinant TFPI (anti-TFPI) using an optimized ELISA. Anti-TFPI (>18 U mL⁻¹ for IgG and/or > 15 U mL⁻¹ for IgM) were detected in 54 patients with aPL (33.3%) and in three out of 79 normal controls (3.8%, P  < 0.0001). Among aPL patients, the prevalence of positive anti-TFPI was 38.3 and 28.4% in those with or without diagnosis of definite antiphospholipid syndrome (APS). Patients with definite APS had a significantly greater frequency of high titer (>50 U mL⁻¹) anti-TFPI than aPL patients from the no definite APS group (18.5% vs. 6.2%, OR 3.7, P = 0.017). Most aPL recognized full-length TFPI, but not a truncated form of TFPI lacking the C-terminus of the molecule. Isolated IgGs from subjects with anti-TFPI impaired the dose-dependent inhibitory effect of TFPI on factor Xa activity in the presence, but not in the absence of phospholipid vesicles. Thus, aPL with high titer anti-TFPI limit TFPI action and are associated with the APS.     

急性心肌梗死患者组织因子及组织因子途径激活抑制物水平的变化

目的探讨急性心肌梗死(AMI)患者组织因子(TF)及组织因子途径激活抑制物(TF-PI)的变化及临床意义。方法用ELISA法分别检测50例AMI患者及20例健康对照的外周血TF及TFPI的抗原水平。比较15例支架手术患者冠状窦内及外周血的TFPI水平。比较并发糖尿病和/或高脂血症AMI患者与无并发症者的TFAg及TFPIAg水平。结果AMI患者的TFAg及TFPIAg较正常人均明显升高(P<0.01);支架患者冠状窦内的TFPI水平明显低于其外周血(P<0.01);有并发症患者的TF及TFPI水平均明显高于无并发症患者(分别为P<0.01和P<0.05)。结论AMI患者外周血凝血活性增高,并发糖尿病和/或高脂血症AMI患者的凝血活性较无并发症患者高,血栓形成使冠状动脉腔内的TFPI消耗而降低。     

体外循环心脏手术术后并发症的影响因素研究

目的：探讨体外循环心脏手术术后并发症的影响因素。方法回顾性分析2009年5月至2013年3月行体外循环心脏手术的203例成年患者的临床资料,分析术后并发症发生情况;根据是否发生术后并发症,将患者分为并发症组和无并发症组,对可能的危险因素进行单因素分析和Logistic多因素回归分析。结果203例患者中,发生术后并发症31例,并发症发生率为15．3％。单因素分析结果显示,年龄大于或等于55岁、体外循环时间大于或等于2 h、主动脉阻断时间大于或等于100 min、心脏功能Ⅳ级以及术前合并原发性高血压、糖尿病、慢性阻塞性肺疾病是诱发术后并发症的相关因素（P＜0．05）。Logistic多因素回归分析结果显示,年龄大于或等于55岁、体外循环时间大于或等于2 h、主动脉阻断时间大于或等于100 min及心脏功能Ⅳ级是导致术后并发症的危险因素（P＜0．05）。结论对于行体外循环心脏手术的患者,应通过术前评估,及时干预可诱发术后并发症的危险因素,从而提高手术安全性和疗效。     

Thrombin generation in factor VIII-depleted neonatal plasma: nearly normal because of physiologically low antithrombin and tissue factor pathway inhibitor

BACKGROUND: Bleeding in hemophilic neonates has a low incidence. A possible explanation for this could be the peculiarities of the neonatal hemostatic system, especially low levels of the inhibitors tissue factor pathway inhibitor (TFPI) and antithrombin (AT). OBJECTIVE: We investigated the influence of an elevation of these inhibitors to adult levels on the thrombin generation (TG) in normal neonatal plasma and factor (F) VIII-depleted neonatal plasma by means of incubation with anti-FVIII-antibodies. PATIENTS/METHODS: TG was measured after activation with low amounts of tissue factor (TF) by using Calibrated Automated Thrombography. RESULTS: TG in FVIII-depleted neonatal plasma was nearly as high as in normal neonatal plasma. TG decreased after elevation of AT in both neonatal plasmas. After elevation of TFPI TG decreased much more in FVIII-depleted neonatal plasma than in normal neonatal plasma. After elevation of both inhibitors their synergistic effect led to a stronger decrease of TG in FVIII-depleted neonatal plasma. TG measured in plasma of one hemophilic newborn showed the same pattern as in FVIII-depleted neonatal plasma. CONCLUSION: Our observation provides a biochemical basis for the rare bleeding in hemophilic neonates and shows the important role of the natural inhibitors in the hemostatic system of hemophilic patients.     

心肺转流术对凝血及血小板功能的影响

目的 应用Sonoclot凝血及血小板功能(Pf)分析仪检测心脏手术心肺转流术(CPB)对Pf的影响.方法 麻醉前病情分极Ⅰ～Ⅲ级,心脏手术患者24例,其中瓣膜置换术12例,室缺修补术12例.采用静吸复合全身麻醉,分别于麻醉诱导后(T1)、肝素化后10 min(3 mg/kg)(T2)、CPB后10 min(T3)及鱼精蛋白拮抗后10 min(T4)抽血,检测激活全血凝固时间(sonACT)、凝血速率(clot rate)和Pf并进行血小板计数(PLT).结果 与T1相比,T2点的clot rate及sonACT明显升高(P＜0.01),PLT和Pf降低(P＜0.05);T3点的sonACT明显延长,clotrate和Pf显著下降,PLT明显降低(P＜0.01);T4点的sonACT明显延长,Pf明显升高(P＜0.01),clot rate无明显变化,PLT显著降低(P＜0.01).结论 CPB可显著影响Pf,心脏手术中监测凝血及Pf有重要的临床意义.     

A GPI-anchored co-receptor for tissue factor pathway inhibitor controls its intracellular trafficking and cell surface expression

BACKGROUND: Tissue factor pathway inhibitor (TFPI) lacks a membrane attachment signal but it remains associated with the endothelial surface via its association with an, as yet, unidentified glycosyl phosphatidylinositol (GPI)-anchored co-receptor. OBJECTIVES/METHODS: Cellular trafficking of TFPI within aerolysin-resistant ECV304 and EA.hy926 cells, which do not express GPI-anchored proteins on their surface, was compared with their wild-type counterparts. RESULTS AND CONCLUSIONS: Although aerolysin-resistant cells produce normal amounts of TFPI mRNA, TFPI is not expressed on the cell surface and total cellular TFPI is greatly decreased compared with wild-type cells. Additionally, normal, not increased, amounts of TFPI are secreted into conditioned media indicating that TFPI is degraded within the aerolysin-resistant cells. Confocal microscopy and studies using metabolic inhibitors demonstrate that aerolysin-resistant cells produce TFPI and transport it into the Golgi with subsequent degradation in lysosomes. The experimental results provide no evidence that cell surface TFPI originates from secreted TFPI that binds back to a GPI-anchored protein. Instead, the data suggest that TFPI tightly, but reversibly, binds to a GPI anchored co-receptor in the ER/Golgi. The co-receptor then acts as a molecular chaperone for TFPI by trafficking it to the cell surface of wild-type cells or to lysosomes of aerolysin-resistant cells. TFPI that escapes co-receptor binding is secreted through the same pathway in both wild-type and aerolysin-resistant cells. The data provide a framework for understanding how TFPI is expressed on endothelium.     

Combined tissue factor pathway inhibitor and thrombomodulin deficiency produces an augmented hypercoagulable state with tissue-specific fibrin deposition.

BACKGROUND AND OBJECTIVE: Tissue factor pathway inhibitor (TFPI) and thrombomodulin (TM) are endothelial-associated anticoagulant proteins thought to control hemostasis in specific vascular beds. Here, we have examined the consequences of TFPI deficiency in the presence of a compounding procoagulant state caused by reduced TM function. METHODS AND RESULTS: TFPI(+/-)/TM(pro/pro) mice are born at less than expected frequency in either TFPI(+/-)/TM(pro/+) or TM(pro/pro) mothers but are born at near the expected frequency in TM(pro/+) mothers. Adult TFPI(+/-)/TM(pro/pro) mice have elevated thrombin-antithrombin complex and increased thrombus volume in an electrical injury model of venous thrombosis. In striking contrast to mice with single deficiency of TFPI or TM, TFPI(+/-)/TM(pro/pro) mice exhibit augmented fibrin deposition not only in the liver, but also in the cerebral microvasculature. CONCLUSIONS: TFPI(+/-)/TM(pro/pro) mice exhibit partial intrauterine lethality when carried by mothers with an underlying prothrombotic state, providing the first experimental evidence in an animal model that TFPI-dependent control of hemostasis in the vascular bed of the placenta fulfills a critical role for successful pregnancy outcome. In addition to the placenta, partial TFPI deficiency interacts with decreased TM function in an organ selective manner to produce fibrin deposition in other specific vascular beds, the liver and brain.     

先兆子痫患者血浆组织因子及其抑制物联合检测的初步应用

目的探讨先兆子痫(PE)患者血浆组织因子(TF)、组织因子抑制物(TFPI)和TF/游离TFPI(f-TF-PI)的变化及其临床意义。方法采用双抗体夹心酶联免疫吸附试验(ELISA)法检测PE患者、正常妊娠晚期孕妇和未怀孕正常体检妇女TFf、-TFPI水平。结果 (1)PE患者与正常妊娠孕妇相比,血浆TF水平明显升高,差异有统计学意义(P<0.01);PE和正常妊娠孕妇与未妊娠妇女相比,血浆TF也明显升高,差异有统计学意义(P<0.01)。(2)PE患者血浆f-TFPI水平明显高于正常妊娠孕妇和未妊娠妇女,差异有统计学意义(P<0.01),但正常妊娠孕妇与未妊娠妇女f-TFPI差异无统计学意义(P<0.05)。(3)PE患者与正常妊娠孕妇和未妊娠妇女相比,TF/f-TFPI显著增加,差异有统计学意义(P<0.05)。结论血浆TF和TFPI与妊娠胎盘形成密切相关,TF、TF-PI及其比值可作为妊娠并发PE的新指标,对于临床上早期诊断和防治PE有重要意义。