常规应用东菱迪芙防治血管常见疾病的疗效观察

目的观察常规应用东菱迪芙防治血管常见疾病的疗效及安全性。方法于2002年3月～2007年3月对血管外科常见疾病309例常规应用东菱迪芙(巴曲酶注射液)予以降纤治疗,住院期间所有患者血浆纤堆蛋白原均控制在60～120mg/dl目标范围,记录患者对东菱迪芙产生的药物不良反应,以及用药前后血常规、凝血四项及血生化全项的变化。结果住院期间所有患者在用药过程中未发现明显的药物不良反应,没有观察到任何出血征兆;用药前后比较,血常规、凝血四项及生化全项各指标均未观察到有统计学意义的变化。结论东菱迪芙具有显著的降纤效果且使用安全可靠,建议针对临床合并高纤堆蛋白原血症的患者可以常规应用东菱迪芙行降纤治疗,从而有利于患者康复。     

Antimetastatic effect of defibrinogenation with batroxobin depends on the natural killer activity of host in mice

Summary Using batroxobin, a thrombin-like enzyme found in snake venom, the effects of defibrinogenation on artificial lung metastasis in mice were studied. The role of natural killer (NK) cells in the inhibitory effects of defibrinogenation on metastasis was also investigated. Artificial lung metastasis experiments were performed by inoculating either B16-F10 cells or B16-BL/6 cells, highly metastatic strains of B16 melanoma cells, into C57BL/6 mice via the tail vein. The administration of batroxobin significantly inhibited lung metastasis, as did NK activity augmented by poly (I) · poly (C) administration. When both batroxobin and poly (I) · poly (C) were administered, lung metastasis was more markedly inhibited. When NK activity was suppressed by administration of anti-(asialo GM₁) antibody, lung metastasis was markedly increased. When batroxobin was administered with anti-(asialo GM₁) antibody, no inhibitory effects on lung metastasis, such as those seen with batroxobin alone, were observed. The administration of batroxobin had no effect at all on spleen lymphocyte NK activity. These results indicated that defibrinogenation due to batroxobin inhibits lung metastasis, and these effects depend on NK activity of the host.Abbreviations used NK natural killer - BU batroxobin units - FCS fetal calf serum     

Bhalternin: Functional and structural characterization of a new thrombin-like enzyme from Bothrops alternatus snake venom

A serine protease from Bothrops alternatus snake venom was isolated using DEAE-Sephacel, Sephadex G-75 and Benzamidine-Sepharose column chromatography. The purified enzyme, named Bhalternin, ran as a single protein band on analytical polyacrylamide gel electrophoresis (SDS-PAGE) and showed molecular weights of 31,500 and 27,000 under reducing and non-reducing conditions, respectively. Its complete cDNA was obtained by RT-PCR and the 708 bp codified for a mature protein of 236 amino acid residues. The multiple alignment of its deduced amino acid sequence showed a structural similarly with other serine proteases from snake venoms. Bhalternin was proteolytically active against bovine fibrinogen and albumin as substrates. When Bhalternin and bovine fibrinogen were incubated at 37 °C, at a ratio of 1:100 (w/w), the enzyme cleaved preferentially the Aα-chain, apparently not degrading the Bβ and γ-chains. Stability tests showed that the intervals of optimum temperature and pH for the fibrinogenolytic activity were 30-40 °C and 7.0-8.0, respectively. Also, the inhibitory effects of benzamidine on the fibrinogenolytic activity of Bhalternin indicate that it is a serine protease. This enzyme caused morphological alterations in heart, liver, lung and muscle of mice and it was found to cause blood clotting in vitro and defibrinogenation when intraperitoneally administered to mice, suggesting it to be a thrombin-like enzyme. Therefore, Bhaltenin may be of interest as a therapeutic agent in the treatment and prevention of thrombotic disorders.     

Defibrinogenation Therapy for Idiopathic Sudden Sensorineural Hearing Loss in Comparison with High-dose Steroid Therapy

Objective--The efficacy of defibrinogenation therapy for idiopathic sudden sensorineural hearing loss was studied in comparison with high-dose steroid therapy.

Material and methods--Eighty-eight consecutive patients with hearing levels >40 dB and who had suffered hearing loss for ≤30 days were enrolled: 40 patients for high-dose steroid therapy (PSL group) and 48 for defibrinogenation therapy (BX group). Hearing recovery was evaluated by grade assessment and by the improvement in hearing compared to the unaffected contralateral ear.

Results--The overall hearing outcomes of the two groups were roughly equivalent. However, with regard to patients with initial hearing levels <80 dB, the hearing improvement rate of the BX group was significantly worse than that of the PSL group (61.2%±7.3% vs 88.7%±8.9%; p<0.05), whereas in patients with initial hearing levels ≥80 dB, the hearing outcomes did not differ between the 2 groups. Three patients in the PSL group manifested hyperglycemia while no serious side-effects were observed in the BX group.

Conclusion--These results indicate that high-dose steroid therapy should be employed in preference to defibrinogenation therapy for patients with moderate hearing loss, whereas defibrinogenation therapy has an advantage for those with severe hearing loss, in view of its lower frequency of side-effects.     

Thrombin-like snake venom proteinases

Proteinases affecting one or several physiological thrombin substrates are current components of Crotalidae and Viperidae venoms. Enzymes causing in vitro coagulation of fibrinogen without affecting other thrombin-susceptible blood constituents as well as enzymes affecting platelets, F. V, VIII and XIII with only minor action on fibrinogen have been isolated. Fibrinogen affecting proteinases may catalyze the release of either fibrinopeptide (Fp) A (e.g. ancrod, batroxobin) or Fp B (Agk. contortrix proteinase) or of both Fp A and B (B. gabonica proteinase). Some of these enzymes are inhibited by AT III-heparin complex (e.g. Agk. contortrix proteinase) some are not inhibited by either AT III-heparin or hirudin (e.g. batroxobin). The application of Fp A releasing venom proteinases into animals causes transformation of fibrinogen into fibrin I monomer which is rapidly degraded by fibrinolysis and thereby leads to a state of afibrinogenaemia. The administered enzyme is gradually bound to serum proteinase-inhibitors and inactivated. A species dependent interaction between venom enzyme, fibrinogen and serum proteinase inhibitors creates specific differences in dose response relationship. Thus, batroxobin isolated from B. moojeni (HOGE) proved to be a superior defibrinogenating agent in man, as compaired to the closely related enzyme isolated from B. atrox (L.). LD₅₀ of B. atrox venom in previously batroxobin defibrinogenated mice is not significantly different as compaired to normal animals, indicating an only minor role of batroxobin in Bothrops venom poisoning.     

竹叶青蛇咬伤中毒至DIC样综合征的临床研究

目的　探讨毒蛇竹叶青咬伤引起DIC样综合征的临床中毒发病机制和治疗方法。方法　对来本院急诊确诊的竹叶青蛇咬伤 16例病人测定抗凝血酶原Ⅲ活性 (antithrombinⅢ ,AT -Ⅲ )、α2 -纤溶酶抑制物活性 (α2 -plasmininhibitor,α2 -PI)、纤维蛋白原浓度 (Fibrinogen ,Fg)和纤维蛋白降解产物含量 (FDP) ,并对治疗前后的检查结果进行对比。常规检查血小板计数 (plateletcount,PLT)和试管法凝血时间 (cruortime ,CT)。结果　治疗前AT -Ⅲ活性 [(5 6 6± 11 17) % ]、α2 -PI活性 [(2 8 4±5 85 ) % ]及Fg含量 (0 5 3± 0 16g/L)均比正常对照组明显减少 (P <0 0 1) ,但α2 -PI活性和Fg含量下降更明显 ;FDP含量(5 7 0± 8 4 8μg/mL)比正常对照组明显增多 (P <0 0 1)。 16例病人中CT延长有 10例 ,PLT低于正常范围有 11例。经治疗病人均痊愈出院 ,但检查发现血液学方面的恢复比较缓慢。结论　竹叶青蛇咬伤可引起病人体内的凝血和纤溶系统异常 ,出现血液脱纤维蛋白原状态的DIC样血液学改变     

The effects of defibrinogenation with batroxobin on endotoxin-induced disseminated intravascular coagulation in rats

Experimental disseminated intravascular coagulation (DIC) can be induced by a 4-hr sustained infusion of endotoxin at a dose of 100 mg/kg in rats. This experimental model of DIC in rats was used to study the effects of defibrinogenation with batroxobin against DIC. One hour before the infusion of endotoxin, 200 batroxobin unit (BU)/kg of batroxobin was injected intraperitoneally. Immediately after the injection, fibrinogen level markedly decreased and fibrinogen and fibrin degradation products increased. Prothrombin time and partial thromboplastin time were also prolonged. Blood counts, platelet counts and hematocrit level only showed a slight decrease after the injection. The preventive effect against DIC was noted by the partial inhibition of the fall in the platelet counts and lessened number of renal glomeruli with fibrin thrombi, in the rats treated with 200 BU/kg of batroxobin 1 hr before the infusion of endotoxin (100 mg/kg/4 hr). From these results, it was shown that fibrinogen metabolism plays an important role in the DIC state.     

Studies on mechanisms involved in metastasis formation from circulating tumor cells

Summary As shown in earlier studies the formation of metastases after i. v. tumor cell injection in rats is increased in the immediate post-traumatic period and treatment with heparin, thrombocytopenia, and defibrinogenation decreases the formation of metastases. Thrombocytopenia also inhibits the stimulating effect of trauma on metastasis formation. The results of the studies reported in this paper show that the changes of metastasis formation induced by the factors mentioned above with few exceptions are well correlated to the lodgement of the injected tumor cells. Thus, heparin treatment and thrombocytopenia decrease the pulmonary lodgement of i.v. injected tumor cells. Trauma increases the pulmonary lodgement of i.v. injected tumor cells but when trauma is combined with thrombocytopenia, the effect of thrombocytopenia dominates and the pulmonary lodgement of tumor cells decreases when compared to control conditions. Despite this, trauma still gives rise to increased tumor cell lodgement during thrombocytopenia.This study was supported by grants from the Göteborg Medical Society