Low‐molecular‐weight heparin in patients with advanced cirrhosis

Background & aims: The use of low‐molecular‐weight heparins (LMWH) in patients with advanced liver diseases is frequently avoided because of the enhanced risk of bleeding complications. However, many patients with impaired liver function are at a high risk of thrombosis or have an indication for therapeutic anticoagulation. Therefore, the aim of this study was to evaluate the pharmacokinetics of LMWH in patients with cirrhosis. Methods: Eighty‐four consecutive patients with cirrhosis and a clinical indication for prophylactic or therapeutic anticoagulation were included. The LMWH doses were chosen according to current guidelines. Antifactor Xa activity (anti‐Xa) was assessed on two consecutive days, 4 h after drug administration. The severity of liver disease was quantified using Child–Turcotte–Pugh score, the MELD score and clinical features and was correlated with the anti‐Xa value and the occurrence of complications. Results: Antifactor Xa activity was negatively correlated with the severity of the liver disease, and a positive correlation was observed between antithrombin‐III (AT) levels and anti‐Xa value. AT itself was negatively correlated with the severity of liver disease. Seven patients had an episode of variceal bleeding. No patient died during the observation interval and no thromboembolic events occurred. Conclusion: Prophylactic use of LMWH in patients with cirrhosis appears to be safe. A decreased anti‐Xa value in cirrhotic patients and a negative correlation with liver function challenge the unconditional use of anti‐Xa assays in LMWH monitoring in cirrhotic patients and reveals a potential limitation of anti‐Xa analysis in these patients. Low levels of AT, because of reduced hepatic synthesis, are the most likely cause of this phenomenon.     

A comparison of antithrombin III procedures

Summary Antithrombin III (AT III) is the most potent physiologic inactivator of thrombin and other serine proteases in the blood clotting mechanism. Hereditary deficiency of this protein is associated with recurrent deep-vein thrombosis that begins in late adolescence. Untreated, this disease may lead to early death from recurrent and massive pulmonary emboli. Attempts to identify groups of patients who are the most likely to develop thromboembolic disease because of an acquired deficiency of AT III have been frustrated by the lack of standardization of the assays and the inability to compare results of the different AT III assays. The functional assays and immunoelectrophoretic determinations do not measure the same component. In order to compare the ability of current AT III procedures to determine levels of AT III in various disease states, we used immunoelectrophoretic, chromogenic, and clottable assays to measure the AT III of patients with congenital AT III deficiency and of patients with possible acquired AT III deficiency.     

Antithrombin III kumamoto II; A single mutation at Arg393-his increased the affinity of antithrombin III for heparin

Abnormal antithrombin III (AT III) was found in a 30-year-old woman who suffered from recurrent thrombosis during pregnancy and the postpartum period. Among her family members, only her father had recurrent episodes of deep vein thrombosis of the lower extremities, from his youth. The antithrombin and antifactor Xa heparin cofactor activities of the proposita's plasma were 61% and 42% of normal, respectively. The progressive antithrombin and antifactor Xa activities were also decreased to 55% and 58% of normal, respectively. The immunoreactive level of AT III was within the normal range (23.1 mg/dl). Analysis of the proposita's plasma by crossed immunoelectrophoresis in the presence or absence of heparin and by affinity chromatography on heparin-Sepharose revealed that the proposita's AT III had apparently normal affinity for heparin. Nucleotide sequencing of 7 exons of the proposita's AT III gene amplified by polymerase chain reaction (PCR) disclosed that the second base of codon 393 comprised both G and A, indicating Arg393-His conversion. The base sequences of exons 1,2,3a, 3b, 4, and 5 were normal, excluding any other mutation. These findings indicated that the proposita's AT III was a variant of AT III at the thrombin binding site and that the proposita was a heterozygote for the abnormality. Heparin affinity of purified abnormal AT III from the proposita's plasma was demonstrated to be increased upon affinity chromatography using heparin-Sepharose, suggesting that the mutation (Arg393-His) per se could possibly increase the affinity of antithrombin III for heparin. For this variant AT III (Arg393-His), the name AT III Kumamoto II is proposed. ©1995 Wiley-Liss, Inc.     

p16基因在原发性肝癌中表达缺损的研究

目的：探讨p16基因的异常表达与原发性肝癌发生、发展的关系。方法：应用PCR、SSCP分析及DNA序列测定技术研究了30例原发性肝癌组织中的p16基因外显子2（E2）的缺损情况。结果：（1）p16基因缺损的检出率与肝癌的肿瘤组织类型无关,在肝细胞癌与胆管细胞癌中p16基因缺损的检出率分别为33．33％和20．00％,两组间无显著差异（P＞0．05）;（2）p16基因缺损率的高低与组织学分级密切相关（P＜0．05）。结论：结果提示p16基因的缺损与原发性肝癌的组织学分级相关,它可能参与原发性肝癌的发生、发展过程。     

肝炎、肝硬变和肝癌大鼠IL-2活性和T淋巴细胞亚群变化

本文用脾细胞增殖法和间接免疫荧光法检测了 DAB 诱发的肝炎、肝硬变和肝癌大鼠 IL-2活性和 T 淋巴细胞亚群。结果显示,在肝炎肝硬变和肝癌期实验组 IL-2活性及辅助 T 细胞(TH)/抑制细胞(TS)比值均显著低于对照组(P<0.05～0.001)。在肝硬变和肝癌期实验组总 T 细胞和 TH 细胞显著少于对照组(P<0.05～0.01),TS 细胞显著多于对照组(P<0.05～0.01)。结果表明:1.肝病越重,IL-2活性越低,T 淋巴细胞亚群变化越明显。2.IL-2活性降低先于 T 淋巴细胞亚群。3.TH 细胞/TS 细胞比值敏感于 T 淋巴细胞亚群。     

Familial Functional Antithrombin III Deficiency

A family with a tendency to thrombosis and decreased antithrombin III (AT III) activity in plasma, but normal immunoreactive AT III is reported. 7 members of the family had the AT III defect, 4 of whom have had thrombotic episodes. The importance of biological determination of AT III when studying patients with recurrent thrombotic episodes is emphasized.     

Routine coagulation assays underestimate levels of antithrombin‐dependent drugs but not of direct anticoagulant drugs in plasma from patients with cirrhosis

There is increasing recognition that thrombotic complications may occur in patients with cirrhosis, and literature on antithrombotic treatment in these patients is rapidly emerging. Due to extensive haemostatic changes in patients with cirrhosis, careful monitoring of anticoagulant therapy may be required. Recent data suggest that plasma levels of low molecular weight heparin (LMWH) are substantially underestimated by the anti‐activated factor X (anti‐Xa) assay in patients with cirrhosis. We studied the in vitro recovery of antithrombin (AT)‐dependent and –independent anticoagulant drugs in plasma from 26 patients with cirrhosis and 30 healthy controls and found substantially reduced anti‐Xa levels when AT‐dependent anticoagulant drugs were added to the plasma of patients with cirrhosis. LMWH (0·2 U/ml) had the poorest recovery in plasma from patients with cirrhosis (0·13 ± 0·06 U/ml, compared to 0·23 ± 0·03 U/ml in controls, P < 0·0001), followed by unfractionated heparin and fondaparinux. In contrast, the recovery of rivaroxaban and dabigatran was identical between patients and controls. These data suggest that the anti‐Xa assay cannot be used to monitor AT‐dependent anticoagulant drugs in patients with cirrhosis, as it substantially underestimates drug levels. The direct factor Xa and IIa inhibitors, however, may be monitored through the respective anti‐Xa and anti‐IIa assays in patients with cirrhosis.     

Hereditary antithrombin III deficiency: case report and review of recent therapeutic advances

We report on a newly diagnosed family with hereditary antithrombin III deficiency, with thromboembolic complications in the propositus. Both the propositus and his asymptomatic sister had decreased plasma levels of antithrombin III antigen and activity (28-52% of normal with good agreement between functional and immunologic assays). The propositus developed deep venous thrombosis, followed by massive pulmonary emboli despite heparin therapy and was treated with streptokinase and heparin with excellent results. Shortly thereafter, small bowel obstruction required surgical intervention, and antithrombin III concentrate, recently available in the United States as an investigational new drug (I.N.D.), was administered with no postoperative thrombotic complications. He was subsequently asymptomatic while on warfarin prophylaxis but twice developed venous thrombosis when he failed to take warfarin. The addition of danazol therapy led to a sustained rise in the antithrombin III level. Each of these therapeutic approaches is discussed and the literature reviewed with emphasis on the newer agents--streptokinase, antithrombin III concentrate, and danazol.     

不同浓度的富马毒素B1对肝癌细胞凋亡的影响

目的探讨不同浓度富马毒素对肝癌细胞凋亡的影响,为进一步研究富马毒素诱导凋亡的机制打下基础。方法利用PI标记的流式细胞术测定不同浓度下富马毒素对体外培养肝癌细胞凋亡率的影响。结果在1.25nmol/ml的富马毒素作用下凋亡率与空白没有差异,在2.5～40nmol/mlFB1的浓度范围内出现了明显的凋亡,随着富马毒素浓度的增加,体外培养的肝细胞凋亡率增加,且凋亡率在15nmol/ml达到高峰。结论富马毒素可导致肝癌细胞凋亡,随着浓度的递增,其凋亡率也随之递增。     

超声引导经皮集束电极射频消融冶疗中小肝癌

目的：探讨超声引导经皮集束电极射频消融(RFA)治疗中小肝癌(直径≤5cm)的疗效。方法：利用RF-2000^TM肿癌射频治疗系统，在B超引导下对29例中小肝癌患者34个肿块进行经皮肝穿刺射频热凝冶疗，并用B超及CT检查以了解RFA治疗效果，随访观察其复发和生存情况。结果：RFA治疗后93．3％(28／30)的肿块血供消失(另4个直径≤3cm的肿块治疗前即无血供)，且94．1％(32／34)的肿块呈完全凝固性坏死。对有血供的2个肿块再次进行了RFA治疗。随防6月～3年，29例中现存活25例，半年生存率100％。存活的25例中，已有6例生存半年，7例生存1年，7例生存2年，5例生存3年。结论：集束电极RFA治疗中小肝癌创伤小，安全，疗效可靠。     

Choice of anticoagulant in a congenital antithrombin III (AT III)-deficient patient with chronic renal failure undergoing regular haemodialysis

Summary We describe a 43-year-old male patient with congenital antithrombin III deficiency requiring haemodialysis due to extension of venous thrombus from recurrent deep vein thrombosis. During dialysis with adequate heparinization, the patient often revealed clot formation in the extracorporeal circuit resulting in unexpected discontinuation of dialysis. When either a combination of antithrombin III concentrate plus heparin or the newly developed synthetic antithrombin preparation, MD805, was infused during dialysis, he could be uneventfully dialysed with either of the two regimens. The functional antithrombin III activity with MD805 increased to the same level as that obtained with antithrombin III concentrate, and it was possible to achieve an antithrombotic effect, as measured from the APTT and thrombin-antithrombin III complex with MD805 during and after dialysis. We thus found that MD805 could be used as an anticoagulant drug when an AT III-deficient patient required anticoagulation in the extracorporeal circulation.     

补气滋阴中药抑制DAB诱导大鼠肝癌的实验研究

为探讨防治肝癌的更有效方法，采用人参、鳖甲、女贞子等补气滋阴中药配成的组方喂养大鼠，观察其对中药组、诱癌组及正常对照组大鼠肝癌的发生率、肝功能及体重的变化。结果中药组癌变率明显低于诱癌组（P＜0．05），中药组较诱癌组肝功能损害程度轻（P＜0．01），各组体重增长以正常对照组最为明显，中药组次之，诱癌组增长不明显，有的甚至下降。提示补气滋阴中药能明显减轻因毒物引起的肝脏损害及抑制二甲基奶油黄诱发大鼠肝癌的发生。     

Low Antithrombin III in Acute Hepatic Failure at Term

2 cases surviving acute fatty liver of pregnancy are reported. Both cases had signs of disseminated intravascular coagulation, and extremely low plasma concentration of antithrombin III. One of the women received antithrombin III concentrate. The rationale of this therapy is discussed.     

Treatment of venous thrombosis in antithrombin III deficient patients with concentrates of antithrombin III

Summary Two patients with familial antithrombin III deficiency developed deep venous thrombosis of the lower limb. The diagnosis of venous thrombosis was made by the indium labelled platelet technique which also allowed for the daily assessment of thrombus size. Each patient received treatment with Warfarin, subcutaneous heparin, and infusions of antithrombin III concentrates. The authors conclude that infusions of antithrombin III concentrates may be of value in limiting the extent of acute thrombosis in patients with a severe deficiency of this protein and may help prevent pulmonary embolism. The haemorrhagic risk of continuing modest doses of heparin with high dose ATIII therapy appears small. In addition to its value in the diagnosis of venous thrombosis the indium platelet technique may give an early indication of thrombus extension and may thus indicate the effectiveness of treatment.     

Participation and interactions of neutrophil elastase in haemostatic disorders of patients with severe infections

The prognosis of septicaemia depends on the occurrence of complications such as shock and coagulation defects. The damage to haemostasis is usually explained by the action of the main coagulation and fibrinolysis enzymes, thrombin and plasmin. This paper presents data concerning the role of a third protease, granulocytic elastase. 82 patients who had been admitted to our hospital with suspected septicaemia were examined. Septicaemia was proven in 22 patients by the growth of microorganisms in blood cultures, and was clinically diagnosed in 9 patients. The plasma levels of neutrophil elastase-like protease complexed to a1antitrypsin (a1AT-ELP) were measured by zone immunoelectrophoresis assay (ZIA). The a1AT-ELP values were significantly increased in the 31 septic as compared to the 51 non-septic patients. In patients with complicated septicaemia, negative correlations of a1AT-ELP with factor XIII and the coagulation inhibitor antithrombin III were demonstrable. Among the patients with septic complications, the 3 who survived exhibited a dramatic decrease of a1AT-ELP, whereas in the other 16 patients who died the levels remained elevated. It might be of therapeutic significance that in 9 patients receiving fresh plasma and AT III-concentrate substitution for DIC the a1AT-ELP levels dropped, whereas they remained high in the other septicaemia patients. There were no correlations between a1AT-ELP and the a2antiplasmin-plasmin complexes (a2AP-P1), but strong correlations with signs of coagulation. The data suggest an interaction of coagulation and elastase release, probably involving the Hageman factor.     

Treatment of venous thrombosis in antithrombin III deficient patients with concentrates of antithrombin III

Summary Two patients with familial antithrombin III deficiency developed deep venous thrombosis of the lower limb. The diagnosis of venous thrombosis was made by the indium labelled platelet technique which also allowed for the daily assessment of thrombus size. Each patient received treatment with Warfarin, subcutaneous heparin, and infusions of antithrombin III concentrates. The authors conclude that infusions of antithrombin III concentrates may be of value in limiting the extent of acute thrombosis in patients with a severe deficiency of this protein and may help prevent pulmonary embolism. The haemorrhagic risk of continuing modest doses of heparin with high dose ATIII therapy appears small. In addition to its value in the diagnosis of venous thrombosis the indium platelet technique may give an early indication of thrombus extension and may thus indicate the effectiveness of treatment.     

Impact of antithrombin Ⅲ on hepatic and intestinal microcirculation in experimental liver cirrhosis and bowel inflammation： An in vivo analysis

AIM: To analyze the hepatic and intestinal microcirculation in an animal model of liver cirrhosis and inflammatory bowel disease (IBD) and to characterize the anti-inflammatory action of antithrombin III (ATIII) on leukocyte kinetics and liver damage. METHODS: Hepatic and intestinal microcirculation was investigated by intravital videomicroscopy. Standardized models of experimental chronic liver cirrhosis and bowel inflammation were employed. Animals were divided into four groups (n = 6/group): controls, animals with cirrhosis, animals with cirrhosis and IBD, animals with cirrhosis and IBD treated with ATIII. RESULTS: Cirrhosis facilitated leukocyte rolling and sticking in hepatic sinusoids (1.91+/-0.28 sticker/microm vs 0.5+/-0.5 sticker/microm in controls, P<0.05). The effect enhanced in animals with cirrhosis and IBD (5.4+/-1.65 sticker/microm), but reversed after ATIII application (3.97+/-1.04 sticker/microm, P<0.05). Mucosal blood flow showed no differences in cirrhotic animals and controls (5.3+/-0.31 nL/min vs 5.4+/-0.25 nL/min) and was attenuated in animals with cirrhosis and IBD significantly (3.49+/-0.6 nL/min). This effect was normalized in the treatment group (5.13+/-0.4 nL/min, P<0.05). Enzyme values rose during development of cirrhosis and bowel inflammation, and reduced after ATIII application (P<0.05). CONCLUSION: Liver cirrhosis in the presence of IBD leads to a significant reduction in mucosal blood flow and an increase in hepatic leukocyte adherence with consecutive liver injury, which can be prevented by administration of ATIII.     

Protein C, antithrombin III and plasminogen: effect of age, sex and blood group

Summary. We conducted a cross-sectional study of antithrombin III (ATIII), protein C (PC) and plasminogen (Plg) concentrations in a population of healthy plasma donors in the Trent Region. The distribution of values for protein C was log normal whereas for ATIII and Plg the distributions were positively skewed and differed significantly from normal and log normal. Males had higher antithrombin III concentrations (mean 1·10 iu/ml, range 0·72–1·65) than females (mean 1·07 iu/ml, range 0·75–1·69) ( P =0·001) and levels increased with age in women. Younger women aged 25–34 had significantly lower plasma concentrations of ATIII compared to males of similar age. For protein C, concentrations were higher in males (mean 1·07 u/ml, range 0·37–2·11) than in females (mean 1·01 u/ml, range 0·59–1·61) ( P <0·001) and levels increased with age in both sexes ( P <0·001). In women, a novel difference in protein C concentration between ABO blood groups was noted. There was no significant difference in plasminogen concentration between males and females, and in women plasminogen decreased with age ( r =–0·205, P <0·001).
We conclude that these variations in ATIII and protein C with age and sex are important considerations in the determination of reference ranges for these proteins.