[Cerebral vascular complication of hyperhomocysteinemia. Controlling thromboembolic complications with folates]. / Accident vasculaire cérébral avec hyperhomocystéinémie. Arrêt des accidents thromboemboliques sous folates.

BACKGROUND: Young patients who experience cardiovascular events may have raised levels of homocysteine. There may be several causes for this hyperhomocysteinemia. CASE REPORT: Cerebrovascular disease occurred in a 40-year-old female smoker with hyperhomocysteinemia. This patient subsequently had several episodes of thromboembolism involving the brain and lower limb arteries. Prothrombin concentration was difficult to control with antivitamin K anticoagulants. Investigations to identify a genetic cause of hyperhomocysteinemia revealed that she was homozygous for the C677T mutation on the methylenetetrahydrofolate reductase gene. There was no G1691A mutation of the factor V gene, a risk factor for familial thrombosis. Supplementation with folic acid successfully halted episodes of thromboembolism (follow-up 2 years) and prothrombin levels stabilized under treatment. DISCUSSION: The C677T mutation, which is common in the general population (15.7%), cannot explain the effect of folate supplementation alone. Other mutations affecting homocysteine metabolism could have a potentializing effect on vascular events.

[The effects of Salvia miltiorrhiza and polysaccharide sulphate on the adhesion of erythrocytes of the patients with cerebral thrombosis to cultured endothelial cells].

Salvia miltiorrhiza and polysaccharide sulphate are commonly prescribed for curing cerebral vascular diseases. In this study, we found that the adhesion of erythrocytes of the patients with cerebral thrombosis to cultured human umbilical vein endothelial cells was decreased in number and intensity after the erythrocytes were treated with salvia miltiorrhiza and polysaccharide sulphate in flow field. Moreover we found that polysaccharide sulphate was more effective than salvia miltiorrhiza in preventing adherence in common doses. The two drugs' effects of preventing adherence might be an important mechanism for curing the patients with cerebral thrombosis.

Effect of dietary docosahexaenoic acid in the rat middle cerebral artery thrombosis model.

We investigated the effect of dietary docosahexaenoic acid (DHA) supplementation on the thrombolytic efficacy of recombinant tissue-type plasminogen activator (rt-PA), platelet aggregability, serum cholesterol and phospholipids. Male Wistar rats (6 weeks old) received dietary DHA supplementation (300 mg/kg per day) for 8 weeks. The rat middle cerebral artery (MCA) was occluded by a thrombus induced by photochemical reaction between rose bengal and green light which cause endothelial damage followed by platelet adhesion, aggregation and formation of a platelet and fibrin-rich thrombus at the site of photochemical reaction. The MCA blood flow was monitored using a laser Doppler flowmeter. rt-PA was administered 30 min after the middle cerebral artery had been occluded by a thrombus. This regimen produced a significant (P < 0.05) decrease in serum free-cholesterol and phospholipids levels, inhibited platelet aggregation ex-vivo induced by collagen in whole blood (P < 0.05), reduced thromboxane (TX) B2 formation (P < 0.01) in whole blood and prolonged the time for thrombotic MCA occlusion (P < 0.01) as compared with values obtained from animals on standard diet. Further, dietary DHA enhanced thrombolytic efficacy of rt-PA and reduced the size of ischaemic cerebral lesions. Our findings suggest that dietary DHA produces antithrombotic effects via metabolic conversion to non-atherogenic and non-platelet stimulant metabolites.

Intravenous aspirin causes a paradoxical attenuation of cerebrovascular thrombolysis.

BACKGROUND AND PURPOSE: Aspirin treatment is recognized as an advantageous adjunct to thrombolytic agents in myocardial infarct patients. In this study we examined the effects of aspirin on the rate of clot lysis and on the frequency and extent of hemorrhagic transformations in rabbit models of embolic stroke. METHODS: Rabbit models of ex vivo platelet aggregation and cutaneous template bleeding times were used to show the anticoagulant effects of aspirin in our experimental paradigm. We monitored tissue-type plasminogen activator (TPA)-induced clot lysis in two rabbit models of embolic stroke by (1) scintigraphically following the dissolution of a 99mTc-tagged clot or (2) using roentgenography to follow the disappearance of an Sn-tagged clot. RESULTS: In animals pretreated (18 hours) with a single administration of aspirin (1, 5, or 20 mg/kg IV) or 1 mg/kg per day for 3 days, the aggregation response of platelets to collagen (3.3 micrograms/mL) or arachidonic acid (0.5 mmol/L) was attenuated. High-dose aspirin also increased ear template bleeding time from 1.6 to 2.6 minutes. When aspirin (20 mg/kg) was administered 18 hours before embolism and subsequent lysis with TPA (0.3 mg/kg bolus; 3 mg/kg per hour IV), the pretreatment significantly antagonized the rate and extent of TPA-induced clot lysis by up to 70%. This was confirmed in a second embolic stroke model. The suppression of TPA-induced lysis was reversed by administration of the prostacyclin analogue iloprost (10 micrograms/kg per hour) directly into the cerebral circulation. CONCLUSIONS: We conclude that aspirin reduces the effects of TPA in embolic stroke models. This effect may be the result of a loss of endothelial prostacyclin production since the effect is reversed by iloprost.

Therapeutic efficacy of tirilazad in experimental multiple cerebral emboli: a randomized, controlled trial.

OBJECTIVE: A significant proportion of patients who undergo cardiac surgery or carotid endarterectomy appear to develop subtle cognitive deficits, with the occurrence of multiple cerebral microemboli documented by Doppler ultrasound during these procedures. We used an experimental multiple cerebral embolism model to test whether treatment with tirilazad (U74006F), a putative inhibitor of lipid peroxidation, would improve functional outcome after multiple brain emboli. DESIGN: Randomized, controlled trial. SETTING: Animal care facility procedure room. SUBJECTS: A total of 44 New Zealand White rabbits weighing 2 to 3.0 kg. INTERVENTIONS: Variable quantities of 125I-labeled 50-microns microspheres were injected via a carotid catheter to produce multifocal brain ischemia. Rabbits randomly received either: tirilazad (3 mg/kg i.v.) 5 mins before embolization (pretreatment), or 30 mins after embolization (posttreatment) followed by 1.5 mg/kg every 5 hrs x 3 doses. A third group received vehicle only (control) 5 mins before, followed by three doses every 5 hrs. MEASUREMENTS AND MAIN RESULTS: The animals were rated by a blinded observer at 18 hrs after ischemia and scored as either grossly abnormal/dead or normal. The animals were killed and the amount of microspheres in the brain that were required to produce abnormal function at 18 hrs was calculated for each group. To determine if tirilazad also modified leukocyte function during ischemia, neutrophil adhesion to laminin was determined at baseline and 18 hrs after ischemia using a myeloperoxidase assay. In this study, pretreatment, but not posttreatment with tirilazad produced a significant reduction in neurologic deficits. Tirilazad also attenuated postischemic increases in neutrophil adhesion. CONCLUSIONS: Tirilazad pretreatment reduces neurologic deficits from multiple cerebral emboli. This significant protective effect suggests that pretreatment with tirilazad may play a role in clinical situations where the risk of cerebral emboli is high, with changes in leukocyte adherence as a potential mechanism.

[Clinical effect and experimental study of xijian tongshuan pill].

Xijian Tongshuan pill (XJTS), consisted of Siegesbeckia orientalis, Moschus moschiferus, Hirudo nipponica, Prunus Persicae, Carthamus tinctoruis, Ligusticum wallichi, Panax notoginseng, Angelica Sinensis, Borneolum, etc, were used in treating 70 patients with cerebral thrombosis. The marked effective rate was 82.9%, total effective rate was 96.7%. In control group A, Dextranum and Venoruton were used, in control group B cyclandelate capsule were used. The marked effective rate was 61.7% and 61.1% respectively, the total effective rate was 81.7% and 83.3%. The differences were significant (P < 0.01). The improvement of blood rheology and CT of brain were also significant (P < 0.01). The experiment proved that XJTS pill could inhibit and delay the thrombosis of rabbit, inhibit the platelet aggregation. Acute and subacute toxicity tests proved that XJTS pill was safe and effective.

[Clinical and experimental research of buyang huanwu tang granule in treatment of ischemic apoplexy].

38 cases of ischemic apoplexy were randomly divided into three groups. Among them 26 cases were treated with type I and type III of Buyang Huanwu Tang Granule (BYHWTG) for 10 weeks, respectively. The other 12 cases served as a control group. The results showed that clinical cure and markedly effective rate were 42.3%, the total effective rate was 88.5% in BYHWTG group. The effective rate of BYHWTG type I for the treatment of ischemic apoplexy was 100% and it was superior to type III (84.6). BYHWTG could significantly improve hemorheologic indexes in the patients of ischemic apoplexy. The activity of RBC sodium pump was markedly raised from 0.210 +/- 0.003 to 0.250 +/- 0.008 1/h (P < 0.001) in BYHWTG type I. The results of this study suggested that BYHWTG had evident efficacy in the treatment of ischemic apoplexy.

[Ischemic apoplexy treated with acupuncture using the principle of replenishing qi and promoting blood circulation].

UNLABELLED: 32 cases of ischemic apoplexy were treated by acupuncture using the principle of replenishing Qi and promoting blood circulation. The clinical efficacy and the change of nail-fold microcirculation and hemorheology before and after the treatment were observed. RESULT: The total effective was 93.75%. Before the treatment, the microcirculation of nail-fold was markedly abnormal, and the criteria of hemorheology was abnormally elevated. But after the treatment, together with the recovery of nail-fold microcirculation and hemorheology, the clinical symptom and sign of the patients also improved. Thus it showed that acupuncture method had the function of changing the microcirculation and the hypercoagulability of the patients' blood, further promote the recovery of the function of affected cerebral tissue.

[Relation between malondialdehyde generation by platelets and plasma thromboxane B2 and diagnostic classification by syndrome differentiation of traditional Chinese medicine in stroke during acute stage].

The malondialdehyde generation by platelets and TXB2 in poor platelet plasma were examined in 36 patients with stroke during acute stage. By CT examination 19 cases were diagnosed hemorrhagic, 17 cases ischemic; while by syndrome differentiation of TCM 16 cases belonged to Zhongzangfu(middle internal organs), 20 cases Zhongjingluo (middle channels). Results showed that the malondialdehyde generation by platelets was reduced, TXB2 in poor platelet plasma increased in patients, compared with those in the healthy controls. This finding was common in stroke during acute stage and was not related to diagnostic classes by either CT examination or syndrome differentiation of TCM. This study indicates that maintenance of normal platelet function may have significant implication in the prevention and treatment of cerebrovascular disease.

[Simultaneous detection of the platelet aggregation and release in patients with cardio-cerebral vascular diseases associated with blood stasis and their clinical significance].

The authors determined the platelet aggregation(PA) activity respectively with electric impedance and photoelectric turbidimetry in patients with ischemic cardio-cerebral vascular diseases associated with blood stasis. The results showed the PA activities were elevated both in whole blood and plasma. Then, the authors detected simultaneously the PA activity and amount of post-aggregation beta-thromboglobulin(beta-TG) releasing and also in vivo amount of spontaneous plasma releasing of beta-TG with photoelectric turbidimetry and RIA methods with blood stasis. The results showed, during the acute phase of stroke, a high activated state of platelet existed, expressed as significant elevation both of the amount of beta-TG releasing of post-aggregation and plasma beta-TG level. However, no definite correlation between rate of PA and subsequent amount of beta-TG releasing was found, and detection of aggregation rate alone did not disclose the state of activation. As compared with the acute phase, during the recovery stage of stroke in which the clinical symptom of blood stasis was improved, the plasma beta-TG level declined significantly, however, was still higher than in normal controls; amount of releasing beta-TG was declining which denoted that the platelet functions were reducing then, but were still in a higher state of activation. These results suggested that there were changes both in number and quality of platelet in patients with blood stasis.

[Clinical and experimental study on cerebral thrombosis treated with antithrombotic xinmaining].

Antithrombotic xinmaining were composed with Moschus, Calculus Bovis, Borneol, Radix Ligusticum, Flos Sophorae Immaturus, Radix Salviae Miltiorrhizae, Leech, etc. This preparation was suitable for treating channels and collaterals type of cerebral thrombosis. The dosage was 2-4 capsules (0.5 g/capsule) oral administration twice per day, 3-4 weeks as a therapeutic course. The authors studied 158 cases of these patients compared with 117 cases of control group with dextran and Vinorutone. The clinical result showed that the obvious effective rate in the therapeutic group was 62.1% and the total effective rate 96.3%; the values in the control group were 38.5% and 86.3% respectively (P less than 0.01). The laboratory results showed that the blood viscosity, serum viscosity, hematocrit (vol %), RBC electrophoresis rate (micron/sec/v/cm) and platelet aggregation rate (%) before antithrombotic xinmaining administration were 5.82 +/- 0.82, 1.82 +/- 0.02, 52.81 +/- 6.70, 0.82 +/- 0.19 and 28.33 +/- 12.02 respectively; and those after the treatment were 4.72 +/- 0.65, 1.70 +/- 0.02, 48.76 +/- 0.40, 0.97 +/- 0.17 and 23.05 +/- 10.01 (mean +/- S), P less than 0.01. The toxicological study proved that the preparation was safe, no significant side-effect and good for cerebral thrombosis medication.

[Comparative study of cerebral infarction treated with acupuncture at 6 acupoints of yang meridian and calan].

UNLABELLED: This article reports the curative effects of acupuncture on 6 acupoints of Yang meridian in treating 32 cases of cerebral infarction in comparison with another 31 cases treated with calan tablets 55 out of 63 patients have been diagnosed as cerebral infarction by computer tomography. Diagnosis of 8 cases relied on history, symptoms, signs together with cerebrospinal fluid examination. Patients were divided randomly into two treatment groups: acupuncture group and calan tablet group. Therapeutic method: (1) For acupuncture group, main acupoints consisted of Jianyu (L.I. 15), Quchi (I. I. 11), Hegu (L. I.4) in the upper extremity and Huantiao (G. B. 30), Yanglingquan (G. B. 34), Guangming (G. B. 37) in the lower extremity. According to the syndrome differentiation, Taichong (Liv. 3), Fengchi (G. B. 20), Tianshu (St. 25), Fenglong (St. 40), Zusanli (St. 36), Sanyinjiao (Sp. 6), Taixi (K. 3) were added. The lifting and thrusting was manipulated. The needles were retained for 30 minutes after the patient felt local sourness, distension and heaviness. Acupuncture was carried out every day for 6 weeks. (2) For calan tablet group, calan tablet 5 mg was administered 3 times a day for the same treatment session as the former group. RESULT: The total effective rates were 93. 75% and 83.87% respectively. The therapeutic effect in the acupuncture group was much better than that in the calan tablet group (P less than 0.05). The majority of hemorheological indices of patients in two groups were obviously higher than those of the normal in the same age group.(ABSTRACT TRUNCATED AT 250 WORDS)