rFVIIa administered by continuous infusion during surgery in patients with severe congenital FVII deficiency

Summary. The use of recombinant FVIIa (rFVIIa) to control bleed in individuals with FVII deficiency has been proven to be effective. The main problems associated with its use are that it requires frequent bolus injections to counteract its short half‐life and high cost. Our study aimed to evaluate whether any advantage could be gained by providing rFVIIa by continuous infusion during surgery with regard to haemostatic efficacy, safety and cost. The prospective study included 10 patients with severe FVII deficiency, who underwent 25 surgical procedures (13 major and 12 minor procedures) and were treated with rFVIIa administered by continuous infusion. Tranexamic acid was given concomitantly every 8 h. Prothrombin time, FVII:C assay and thrombin generation assay were used to monitor the treatment. The mean total dose given was 10 mg during a major surgery and 4.4 mg during a minor surgery for a mean treatment duration of 7.5 and 4.0 days respectively. This corresponds to a reduction of 70–90% in drug usage and medication cost compared with bolus injections. Except for one major perioperative bleeding, excellent haemostasis was achieved in all procedures. One patient developed a transient inhibitory activity. None of these events affected the postoperative course or prolonged the hospital stay. Our study demonstrated that continuous infusion of rFVIIa during surgery is safe, effective and highly cost effective.     

The P303T mutation in the human factor VII (FVII) gene alters the conformational state of the enzyme and causes a severe functional deficiency

We report the results of in vitro expression and biochemical characterization of the naturally occurring type II mutation Pro303Thr (P303T) in the factor VII (FVII) gene. Recombinant activated mutated FVII (FVIIa303T), compared with the activated wild-type FVII (FVIIaWT), showed reduced amidase activity toward synthetic substrates, especially when the observed reduced binding affinity for human soluble tissue factor (TF) (K(d) from 4.4 nmol/l for FVIIaWT to 17.3 nmol/l for FVIIa303T) was overcome by a fully saturating TF concentration. Likewise, factor X (FX) hydrolysis by FVIIa303T showed a reduced activity in the absence (and more severely in the presence) of TF (k(cat)/K(m) from 2.3 x 10(7)/mol/l s for FVIIaWT to 8.7 x 10(5)/mol/l s for FVIIa303T). These results showed that the mutant FVIIa is more shifted toward a zymogen-like form compared to FVIIaWT, suggesting that P303 facilitates the conformational transitions that stabilize the active form of FVIIa. The alteration of these allosteric equilibria is especially evident in the presence of TF, which was unable to shift the equilibrium toward a fully active FVIIa form. Additional experiments showed that both TF-catalysed FVII303T autoactivation and FVII303T activation by activated FX in the presence of TF were severely impaired, mainly because of an increase of the K(m) value. Altogether, these defects may explain the severe bleeding symptoms in a patient carrying the FVIIP303T mutation.     

Molecular defects in CRM+ factor VII deficiencies: modelling of missense mutations in the catalytic domain of FVII

Summary. The molecular defects causing CRM+ factor VII deficiency were investigated in seven unrelated subjects and several members of their families.
Four missense mutations located in the catalytic domain of factor VII were found. The previously reported ³⁰⁴ArgGln substitution was present in the homozygous and heterozygous forms, with different polymorphic haplotypes, thus demonstrating that it is recurrent and frequent in the Italian population. The ³¹⁰Cys Phe substitution was found in the homozygous form and in the compound heterozygous condition with the nonsense mutation ³⁵⁶Trpstop. Two missense mutations, ²⁹⁸MetIle and ³⁴²GlyArg, were found in the homozygous and in the heterozygous condition respectively.
Molecular heterogeneity was further increased by finding of the ³⁵³ArgGln polymorphism in the doubly heterozygous condition with the 304 and 342 mutations.
Plausible explanations for loss of FVII function were found by inspecting a model of the serine protease domain of factor VIIa. Inefficient activation of the catalytic site is predicted for ²⁹⁸MetIle. ³⁴²GlyArg would directly distort the geometry of the 'oxyanion hole'preventing formation of a substrate enzyme intermediate. ³¹⁰Cyshe is predicted to have an adverse effect on tissue factor interaction. These mutations point to important regions of the factor VII molecule.     

Disorders of menstruation and their effect on the quality of life in women with congenital factor VII deficiency

AIMS AND OBJECTIVES: To review menstrual problems in women with congenital FVII deficiency and to study their effect on the quality of life during menstruation in women with congenital FVII deficiency. METHOD: 14 women with congenital factor VII deficiency registered with the Haemophilia Centre at the Royal Free Hospital were interviewed and their case notes reviewed. All women completed Pictorial Blood assessment Chart (PBAC) for assessment of menstrual blood loss and a quality of life questionnaire during menstruation. Similar questionnaire and PBAC was completed by an age matched healthy control group of 23 women. RESULTS: Median age of study group was 35 yrs and of control group 34 yrs. Median FVII level of the study group was 31.5 IU/dL Two women had severe FVII deficiency (FVII level < 10 IU/dL) and 12 women had mild-moderate FVII deficiency. 57% women (8/14) from study group had menorrhagia (PBAC score > 100) compared with 17% (4/23) women from the control group. Six women (43%) from the study group were diagnosed with anaemia due to heavy periods, compared to two (9%) in the control group. The quality of life scores during menstruation were significantly worse in the women with FVII deficiency, compared to controls. CONCLUSION: Women with factor VII deficiency exhibit a spectrum of bleeding symptoms, menorrhagia being one of the commonest symptoms. This has adverse effect on their quality of life.     

庚型肝炎病毒在不同型肝病患者肝组织中免疫组化检测

应用免疫组化以非编码区抗－ＨＧＲＶＮＳ５单克隆抗体,ＰＡＰ和ＡＢＣ法分别对４２例急慢性肝炎患者肝组织ＨＢｓＡｇ,ＨＢｃＡｇ,ＨＣＶＮＳ３Ａｇ及ＨＧＶＮＳ５Ａｇ免疫组化检测,结果ＨＧＡｇ阳性１５例,占３５．７％,各型肝病间ＨＧＡｇ检出率无明显差异,光镜观察到特异染色呈棕黄色或黄色细颗粒状,主要定位于肝细胞浆,部分同时核型表达,有４例单纯核型表达,ＨＧＡｇ阳性肝细胞多在假小叶中大片灶状范围分布,大多散     

The effect of tissue factor concentration on calibrated automated thrombography in the presence of inhibitor bypass agents

Thrombin generation has been suggested as a method to monitor treatment with factor eight inhibitor bypassing activity (FEIBA) or recombinant FVIIa (rFVIIa). The sensitivity of the assay for individual coagulation factors is dependent on the tissue factor (TF) concentration. An inverse relation between the rFVIIa concentration needed to shorten the clotting time and TF concentration has been shown but the data on thrombin generation are inconsistent. Information on TF concentration in measurements with FEIBA is limited. We studied the influence of TF concentration (1 and 5 pM) on thrombin generation through spiking experiments with rFVIIa and/or FEIBA in the plasma of severe haemophilia A patients and after four and three treatment episodes, respectively, using the calibrated automated thrombin generation assay (CAT) in platelet poor plasma. Spiking with FEIBA showed a linear relation with the endogenous thrombin potential (ETP)/peak at 1 pM but substrate depletion at 5 pM. Spiking with rFVIIa showed a near linear dose-response relation with the ETP/peak at 1 pm but only a shortening of the initiation phase at 5 pM. Similar effects were present in post-treatment samples. FEIBA acted synergistically with rFVIIa. This suggest a role for CAT in monitoring inhibitor bypass treatment but low TF concentrations are required to avoid substrate depletion with FEIBA and to demonstrate the effect of rFVIIa.     

冠心病患者血浆组织因子和组织因子途径抑制物的变化

目的 :通过检测不同类型冠心病 (CHD)患者血浆组织因子 (TF)和组织因子途径抑制物 (TFPI)水平变化 ,探讨其在CHD发病过程中的作用。方法 :以酶联免疫吸附测定法测定CHD患者血浆中TF和TFPI抗原水平。结果 :不稳定型心绞痛 (UAP)和急性心肌梗死 (AMI)患者的血浆TF和TFPI水平与正常对照者和稳定型心绞痛 (SAP)患者相比均有显著性增高 (P <0 .0 5 ) ,以AMI患者尤为明显 (P <0 .0 1) ;UAP和AMI患者的TF PI/TF比值显著降低 (P <0 .0 5 ) ,而SAP患者的上述指标与正常对照者相比 ,其差异均无显著性意义 (P >0 .0 5 )。结论 :UAP和AMI患者TFPI/TF系统失衡 ,标志高凝状态的存在 ;TF和TFPI在这两种类型CHD的发病机制中可能起着重要的作用     

维生素E对组织因子及其抑制物在冠心病中的干预作用

目的 :探讨冠心病 (CHD)的不同类型中血浆组织因子 (TF)及其抑制物 (TFPI)含量的差异变化及维生素E对急性心肌梗死 (AMI)干预作用。方法 :用ELISA方法检测CHD患者 [包括稳定型心绞痛 (SAP)、不稳定型心绞痛 (UAP)、AMI]入院时及治疗 2周时血浆TF、TFPI含量。结果 :①SAP组血浆TF、TFPI水平及TF/TF PI比值均高于正常对照组 ,但差异无统计学意义 (P >0 .0 5 ) ,且治疗前后无明显变化 (P >0 .0 5 )。②UAP组、AMI组血浆TF、TFPI水平及TF/TFPI比值明显高于正常对照组 ,差异有统计学意义 (P <0 .0 1) ,但两组常规治疗前后差异无统计学意义 (P >0 .0 5 )。③AMI加维生素E组干预治疗后TF值显著下降 (P <0 .0 1) ,与正常对照组比较差异无统计学意义 (P >0 .0 5 ) ,TFPI干预治疗后无明显变化 (P >0 .0 5 ) ,而TF/TFPI比值明显降低 (P <0 .0 1)。④各组TF与TFPI呈明显正相关 (P<0 .0 5 ,r=0 .4 32 )。结论 :TF及TFPI在CHD尤其是急性冠状动脉综合征的发生中起重要作用 ,维生素E的干预显著降低患者血浆TF水平 ,降低TF/TFPI比值而对TFPI无影响。     

Role of clinical and laboratory parameters for treatment choice in patients with inherited FVII deficiency undergoing surgical procedures: evidence from the STER registry

Perioperative bleeding is a major concern in patients with factor VII (FVII) deficiency. Evaluating data of 95 FVII‐deficient patients undergoing 110 surgical procedures (61 major, 49 minor), we assessed the impact of type of surgery, bleeding phenotype and FVII coagulant activity (FVII:C) levels on perioperative replacement therapy (RT). Compared to those with higher FVII:C levels, patients with <3% FVII:C received a higher number of RT doses (8 vs. 2, P = 0·003) for a longer RT duration (3 days vs. 1 day, P = 0·001), with no difference in RT dose. Similarly, patients with a history of major bleeds received a higher number of RT doses (8·5 vs. 2–3, P = 0·013) for a longer RT duration (2 days vs. 1 day, P = 0·005) as compared to those with a history of minor bleeds or to asymptomatic patients. No difference in RT was found among major and minor surgical procedures. Overall, multivariate analysis showed that history of major bleeding was the only independent predictor of number of RT doses (β = 0·352, P = 0·001) and RT duration (β = 0·405, P = 0·018). Overall, a ≈20 μg/kg perioperative RT was efficacious in 95·5% of cases. The infusion should be repeated ≈8 times in high‐risk subsets (i.e. patients with a history of major bleeding).     

Use of thromboelastography and thrombin generation assay to predict clinical phenotype in patients with severe FVII deficiency

Bleeding tendency is weakly correlated with the activity of factor VII (FVII) in the plasma of patients with FVII deficiency. A laboratory method for predicting bleeding risk in patients with this coagulation disorder is lacking. We investigated whether global coagulation assays, specifically thromboelastography (TEG) and thrombin generation assay (TGA), could be used to predict bleeding risk. We also sought to identify factors that may explain the differences in bleeding phenotype observed among individuals with severe FVII deficiency. The study comprised 12 patients with severe FVII deficiency (FVII activity <1%). Eleven patients were homozygous for the Gln100Arg mutation and one patient was compound heterozygous. Clinically, 10 patients had increased haemorrhagic diathesis, whereas two patients were asymptomatic. Blood sampling was performed at baseline for TEG and TGA analyses. The platelet aggregation assay was performed and the plasma level of anticoagulation inhibitors and thrombophilic risk factors assessed. No difference in the TEG and TGA results was observed in all FVII‐deficient individuals. The level of free tissue factor pathway inhibitor was within the normal range and similar in symptomatic and asymptomatic subjects. None of the participants had the FV Leiden mutation, prothrombin gene mutation, or abnormal anticoagulant inhibitor levels. Asymptomatic subjects showed normal platelet aggregation. These data suggested that TEG and TGA were not suitable methods for predicting the clinical phenotype in FVII‐deficient subjects.     

Genomic mutations associated with mild and severe deficiencies of transcobalamin I (haptocorrin) that cause mildly and severely low serum cobalamin levels

Transcobalamin (TC) I deficiency, like the function of TC I itself, is incompletely understood. It produces low serum cobalamin levels indistinguishable from those of true cobalamin deficiency. Diagnosis is especially elusive when TC I deficiency is mild. To provide new, more substantive definition, the TCN1 gene was examined in two well-characterised families that included members with both severe and mild TC I deficiencies. A severely deficient proposita with undetectable TC I levels displayed compound heterozygosity for two mutations, each causing a premature stop codon. Relatives in both families who had mildly low or low-normal plasma levels of TC I and cobalamin were heterozygous for one or the other of these mutations. An unrelated patient with mild TC I deficiency and unknown familial TC I and cobalamin status was then tested and found to be similarly heterozygous for one of the mutations. The two nonprivate mutations identify a genetic basis for TC I deficiency for the first time. They also add new approaches to studying mild and severe TC I deficiency and to reducing confusion of its low cobalamin levels with those of cobalamin deficiency and its often dramatically different prognosis and management.     

应用离心管技术以异体微粒软骨脱细胞基质为支架体外构建组织工程软骨

目的将软骨细胞与异体软骨微粒脱细胞基质相结合．构建组织工程软骨。方法分别利用氯化钾、胰蛋白酶和乙二胺四乙酸钠对绵羊关节软骨进行脱细胞，并制成直径0．100—0．154mm的微粒。先分离异体关节软骨细胞并进行体外扩增，再将异体软骨细胞与软骨微粒脱细胞基质混合培养，离心后应用离心管体外培养。结果本脱细胞方法可以使关节软骨细胞完全脱落，且软骨细胞紧紧围绕于异体软骨微粒脱细胞基质四周，生长和分泌功能良好。结论软骨细胞与异体软骨微粒脱细胞基质有良好的生物相容性．可于体外形成软骨样组织。     

厄贝沙坦对心肌梗死后大鼠心肌组织因子和组织因子途径抑制物的影响

目的观察大鼠心肌梗死后心肌组织因子（TF）和组织因子途径抑制物（TFPI）的mRNA表达及厄贝沙坦对其的影响。方法通过结扎大鼠左冠状动脉前降支建立大鼠急性心肌梗死模型组,另设假手术组（20只）。模型组术后24h存活大鼠随机分为安慰剂组（20只）和厄贝沙坦组（50mg·kg^-1d^-1,20只）。用药4周后处死各组大鼠并分别称其心室重量,计算左心室重量指数及心肌梗死面积,应用反转录聚合酶链反应（RT—PCR）方法检测心肌TFmRNA和TFPImRNA。结果模型组左心室重量指数大于假手术组（F=7．83,P〈0．05）。模型组内药物组左心室重量指数明显低于安慰剂组（F=8．96,P〈0．05）,心肌梗死面积比较差异无统计学意义（F=0．96,P〉0．05）;模型组TFmRNA、TFPImRNA表达均高于假手术组（F：8．24,P〈0．05）,其中药物组＇IFmRNA较安慰剂组明显降低（F=8．57,P〈0．05）,药物组TFPI mRNA较安慰剂组增加（F=1．35,P〉0．05）。结论大鼠心肌梗死后心肌TF mRNA、TFPI mRNA表达均明显增高。厄贝沙坦可显著降低心肌梗死大鼠心肌TF mRNA的表达。     

Factor VII deficiency: clinical manifestation of 717 subjects from Europe and Latin America with mutations in the factor 7 gene

Summary.  The congenital FVII deficiency (FVIID) is a rare haemorrhagic disorder with an autosomal recessive pattern of inheritance. Data on phenotype and the genotype from 717 subjects in Central Europe (six countries), Latin America (Costa Rica, Venezuela) and United States, enrolled in the Greifswald Registry of FVII Deficiency were analysed. We detected 131 different mutations in 73 homozygous, 145 compound heterozygous and 499 heterozygous subjects. Regional differences were observed in the mutation pattern and the clinical profile of the evaluated patients. Seventy-one per cent of homozygous and 50% of compound heterozygous subjects were symptomatic. The clinical manifestations of the homozygous subjects were characterized by intracranial haemorrhage (2%), gastrointestinal bleeding (17%), haemarthrosis (13%), epistaxis (58%), gum bleeding (38%), easy bruising (37%), haematoma (15%), haematuria (10%) and menorrhagia (19 of 26 females, 73%). The clinical variability and genotype–phenotype correlation was evaluated in the homozygous subjects. The pattern of bleeding symptoms among compound heterozygous patients was severe and similar to that of the homozygous patients. The large-scale analysis of 499 heterozygous subjects shows that 93 (19%) presented with spontaneous bleeding symptoms such as haemarthrosis (4%), epistaxis (54%), gum bleeding (14%), easy bruising (38%), haematoma (23%), haematuria (5%) and menorrhagia (19 of 45 females; 42%). The severe haemorrhages – intracranial and gastrointestinal – were not reported in heterozygous subjects. The clinical variability and the regional differences in the mutation pattern are discussed regarding care and treatment.     

组织运动瓣环位移技术评价老年双腔起搏器患者不同部位起搏与预后关系

目的 探讨右心室中位间隔面及心尖部起搏下组织运动瓣环位移（TMAD）及N末端B型利钠肽（NT-proBNP）水平与患者预后的关系.方法 2009年3月至2012年1月植入DDD起搏器老年患者148例为研究对象,选择右心室中位间隔部起搏患者（RVMSP组）56例、右心室心尖部起搏患者（RVAP组）42例,观察2组患者术前、术后6、18个月心电图QRS时限,采用TMAD技术检测二尖瓣环六个位点二尖瓣环位移（MADseg）、整体位移（MADglobal）,采用M型超声检测左心室收缩期同步性指标TAS-POST以及双平面法测量左心室射血分数（LVEF）,实验室检查NT-proBNP、测量左心室舒张末期容积（LVEDV）以及出现心血管事件包括心室高频事件（VHR）等指标.结果 所有患者均顺利完成手术,按期随访.2组心血管事件发生率比较,RVAP组最高（P＜0.05）,2组VHR差异无统计学意义（P＞0.05）;与术前比较,RVMSP组患者术后6、18个月NT-proBNP、LVEF、LVEDV等均无变化,RVAP组NT-proB-NP、LVEF、LVEDV无变化,二尖瓣环各位点MAD以及二尖瓣环MADgloba降低,TAS-POST增加（P＜0.05）.术后18个月RVAP组NT-proBNP增加,LVEDV值增加（P＜0.05）,差异有统计学意义（P＜0.05）,LVEF无变化.结论 RVMSP心血管事件发生率较低,不影响患者心功能,为较理想起搏部位,TMAD可早期监测心功能受损,为起搏器患者早期心功能异常的检测提供新的方法.     

钙、维生素D缺乏大鼠长骨成骨细胞的维生素D受体水平

对正常、钙缺乏和维生素D缺乏的大鼠 ,观察其体外培养的长骨成骨细胞的维生素D受体最大结合容量 ,结果显示维生素D缺乏组显著低于正常组 (P <0 .0 1)。     

Flow cytometric analysis of tissue factor (TF) expression on stimulated monocytes — comparison to procoagulant activity of mononuclear blood cells

Summary Whereas tissue factor (TF), a 47 kDa transmembrane glycoprotein, is constitutively present in certain tissues such as epithelial tissue, brain, and placenta, it is normally not expressed by cells within the vasculature. However, inflammatory mediators including bacterial lipopolysaccharide (LPS) can stimulate the expression of cell surface procoagulant activity (PCA) on monocytes. In our present study the kinetics (over 24 h) of molecular TF expression on LPS-stimulated monocytes analyzed by flow cytometry corresponds closely to functional PCA of human mononuclear blood cells (MBC). Both PCA and TF expression on monocytes were rapid events reaching their maximum after about 6 h of stimulation. At this time approximately 70–80% of monocytes had also achieved maximum anti-TF MAb receptor density. For certain analytical applications, monitoring of molecular TF expression on monocytes by flow cytometry using anti-TF MAb is favorable because there is no influence by PCA inhibitors.