Effect of vinpocetin on the hemorheologic parameters in patients with chronic cerebrovascular disease

INTRODUCTION: Data collected from large number of multicenter, randomized trials in acute and chronic stroke patients provide evidence, that incidence and high mortality of cerebrovascular disorders can be decreased mainly by prevention and that the effectiveness of acute stroke treatment is limited. The terminology of "chronic cerebrovascular diseases" involves many pathologic entities and often atypical clinical symptoms refer to the focal or global hypoperfusion of the brain. However, hemorheological disturbances seem to be important factors of the complex pathomechanism. Vinpocetine has successfully been used in the treatment of cerebrovascular diseases, the part of the mechanism of action are the favourable rheological effects demonstrated after oral administration in more previous studies. AIMS AND METHODS: In this study the hemorheological changes after administration of small (30 mg/day) and high dose (increased to 70 mg/day) intravenous vinpocetine for 7 days in 30 patients in chronic phase of ischemic cerebrovascular disease were investigated. RESULTS: High dose parenteral vinpocetine treatment significantly (p < 0.05-0.005) decreased the hematocrit, the whole blood and plasma viscosity and red blood cell aggregation compared to the values before the treatment. Only red blood cell aggregation was improved significantly (p < 0.05) by small dose treatment. CONCLUSION: This study and other hemorheological studies in cerebrovascular patients demonstrated persistent rheological abnormalities despite the preventive therapy. The beneficial rheological effect of high dose parenteral vinpocetine indicates the use of this drug in the treatment of chronic cerebrovascular diseases.     

Cerebral uptake and metabolism of (11C) Vinpocetine in monkeys: PET studies]

Vinpocetine, a vinca alkaloid, is a therapeutic agent widely used in the treatment of acute and chronic stroke patients. To explore the uptake and distribution of vinpocetine in the primate brain, vinpocetine was labelled with 11C and positron emission tomography (PET) was used to measure the uptake and distribution of 11C-vinpocetine in the brain and the trunk of a cynomolgous monkey. HPLC was used to determine the concentration of vinpocetine and its labelled metabolites in blood and plasma. Following the radioligand's intravenous administration, after an initial peak, the total concentration of radioactivity in blood was relatively stable with time. The uptake of 11C-vinpocetine into the brain was rapid and about 5% of the total injected radioactivity was present in the brain two minutes after drug administration. These facts indicate that the compound passes the blood-brain barrier readily and enters the brain. The radioactivity uptake was heterogeneously distributed among brain regions. The highest concentrations were found in the thalamus, the basal ganglia and certain neocortical regions. In an earlier PET investigation on chronic stroke patients the highest increases in cerebral blood flow and glucose metabolism after intravenous vinpocetine treatment occurred in these anatomical structures. The heterogenous regional distribution of vinpocetine and the observation that the highest uptake values in brain structures go parallel with the greatest regional blood flow and glucose metabolic rate increases indicate that direct CNS effects of vinpocetine should be considered as an explanation for the therapeutic effects. The confirmation of this suggestion requires further investigations.     

Cerebral uptake and regional distribution of [11C]-vinpocetin after intravenous administration to healthy men: a PET study

INTRODUCTION: Vinpocetine is a compound widely used in the prevention and treatment of cerebrovascular diseases. The exact mechanism of action of the drug is still not known. The objective of the present investigation was to determine the global uptake and regional distribution of radiolabelled vinpocetine in the human brain. Three healthy persons were examined with positron emission tomography (PET) and [11C]-vinpocetine. RESULTS: The uptake of [11C]-vinpocetine in brain was rapid and on average as a maximum 3.7% of the total radioactivity injected was in the brain 2 minutes after radioligand administration. The uptake was heterogeneously distributed among brain regions. When compared with the cerebellum, an a priori reference region, the highest regional uptake was in the thalamus, the upper brain stem, the striatum and the cortex. CONCLUSIONS: The brain regions showing increased uptake in the human brain correspond to those in which vinpocetine has previously been shown to induce elevated metabolism and blood flow by PET clinical studies in patients with chronic ischaemic post-stroke condition.     

The use of vinpocetine in chronic disorders caused by cerebral hypoperfusion

The clinical signs and symptoms of so-called "cerebrovascular insufficiency" or "cerebral vascular dysfunction" have the characteristics of those of chronic cerebral hypoperfusion. The clinical features of chronic cerebral hypoperfusion often show the symptoms of cognitive impairment and organic psychosyndromes. Cerebral hypoperfusion could be found in dementias of different origin (subcortical arteriosclerotic leucoencephalopathy [Binswanger], vascular dementia, Alzheimer's disease, etc.). Pathological changes caused by chronic cerebral hypoperfusion often confined only to the white matter (demyelisation, glial activation, damage of oligodendroglial cells, as well as scattered cell death). Each therapy has an influence on the biochemical and pathophysiological alterations caused by chronic cerebral hypoperfusion can be used with reason in these disorders. The mechanism of action of vinpocetine is interfering on many aspects with the biochemical and pathophysiological processes attributable to chronic cerebral hypoperfusion, independently of the original alteration responsible for hypoperfusion. This fact might give an explanation on the beneficial effect of vinpocetine on clinical signs and symptoms of chronic cerebrovascular insufficiency.     

The effect of a single-dose intravenous vinpocetine on brain metabolism in patients with ischemic stroke

The effect of a single-dose i.v. infusion of vinpocetine on the cerebral blood flow (CBF) and glucose metabolism of post-stroke patients was studied by measuring the regional and global cerebral metabolic rates of glucose (CMRglu) and the corresponding kinetic constants before and after treatment. Transcranial Doppler (TCD) and single photon emission tomography (SPECT) measurements were also performed. The cerebral glucose metabolism was significantly higher in the contralateral hemisphere than in the affected one before therapy. In the affected hemisphere the regional glucose metabolism was inhomogenous: relatively low values were measured in the stroke region, whereas it was increased in the peristroke region. Although a single-dose vinpocetine treatment did not affect significantly the regional or global metabolic rates of glucose, the glucose transport (both intracellular up-take and release) was strongly affected in the whole brain, in the contralateral hemisphere and in the peri-infarct area of the symptomatic hemisphere. A slightly increased (not significant, N. S.) cerebral blood flow could be observed in the contralateral and a decreased flow (N. S.) in the symptomatic hemisphere.     

Scavenger effect of various cerebrovascular drugs

INTRODUCTION: Oxygen free radicals play an important role in several physiological and pathophysiological processes. In pathological circumstances they can modify and damage biological systems. As oxygen free radicals are involved in a wide range of diseases (cerebrovascular, cardiovascular, etc.), scavenging these radicals should be considered as an important therapeutic approach. AIM: In our in vitro study the antioxidant capacity of three cerebrovascular drugs (pentoxiphylline, piracetam and vinpocetine) was investigated. METHODS: Phenazine methosulphate (PMS) was applied to generate free radicals and thus increased red blood cell rigidity. Filtration technique and potassium leaking were used to detect the cellular damage and the scavenging effect of the examined drugs. RESULTS: At therapeutic serum concentration only vinpocetine had significant (p < 0.01) scavenging activity which protective effect was even better at higher concentrations. Pentoxiphylline and piracetam did not have significant antioxidant capacity at therapeutic concentrations, but increasing the concentrations (pentoxiphylline at hundred times, while piracetam at ten times higher concentrations) led to a significant (p < 0.01) scavenger effect. CONCLUSION: The authors' findings suggest that this pronounced antioxidant effect of vinpocetine and even the milder scavenging capacity of piracetam which tends to cumulate in the cerebral tissue may be of value in the treatment of patients with cerebrovascular disorders.     

Effects of cardiovascular risk factors on hemorheologic parameters in cerebrovascular patients

INTRODUCTION: Hemorheological factors are of significance in the determination of flow characteristics of blood and play an important role in the pathogenesis of cerebrovascular diseases. AIMS AND METHODS: In this study the changes of rheological factors--hematocrit (Hct), plasma fibrinogen concentration (PFC), whole blood (WBV) and plasma viscosity (PV), red blood cell aggregation (AI) and deformability and the association between these parameters and cardiovascular risk factors were investigated in 297 patients (173 males, 124 females, mean age: 60 11 years) with chronic phase (3 months after onset) ischemic cerebrovascular diseases, and in 68 healthy volunteers (30 males, 38 females, mean age: 36 6 years). RESULTS: All investigated hemorheological factors were significantly (p < 0.05-0.0001) elevated in cerebrovascular patients compared to normal controls, the rise in Hct, WBV and PV are some of the most prominent findings. In the group of hypertensive, hyperlipidemic patients, smokers and alcoholics Hct, PFC, WBV, PV and AI were significantly (p < 0.05-0.0001) higher compared to healthy controls, the same factors except plasma fibrinogen concentration showed association with diabetic history. Comparing cerebrovascular patients with or without risk factors, the most severe hemorheological deficit was observed in patients with hyperlipidemia and smoking habits. CONCLUSIONS: In this study the authors proved in chronic ischemic cerebrovascular patients that hemorheological abnormalities persist in most cases for a long time after an acute stroke, significant correlation could be seen between blood rheology and cardiovascular risk factors. Examination of rheological parameters can support to choose the optimal medical treatment in the secondary prevention of stroke, correction of hemorheological disturbances can reduce the risk of recurrent stroke.     

The use of erythtropoietin in cerebral diseases

Global and focal cerebral ischemia is followed by a secondary damage characterized by oxidative stress, excitotoxicity, inflammation and apoptosis. Erythropoietin (EPO) exerts antiapoptotic, anti-inflammatory, antioxidative, angiogenetic and neurotrophic properties. Its potential therapeutic role has been demonstrated in several animal models of cerebral ischemia and also in a clinical trial of ischemic stroke, so it could be considered an ideal compound for neuroprotection in ischemic stroke and in cardiac arrest. Intracerebral hemorrhage (ICH) is the least treatable form of stroke; the mechanisms involved in the secondary brain injury include hematoma mass effect, neuronal apoptosis and necrosis, inflammation. It has been demonstrated in an experimental ICH that EPO intervenes in the inflammatory process, reduces brain water content, hemorrhage volume and hemispheric atrophy, promotes cell survival, preserves cerebral blood flow, has antiapoptotic protective function against oxidative stress and excitotoxic damage. EPO can attenuate acute vasoconstriction and prevent brain ischemic damage in subarachnoid hemorrhage. The neuroprotective function of EPO has been studied also in traumatic brain injury: it reduces the inflammation and improves cognitive and motor deficits. The authors review some of the physiological actions of EPO in the physiopathology of ischemic and hemorrhagic stroke, subarachnoid hemorrhage and brain trauma, and its potential usefulness in the brain injured patient management.     

Retrospective analysis of the effect of vinpocetine infusion in ophthalmologic disorders

Retrospective analysis of the effect of vinpocetine infusion in ophthalmologic disorders. The authors retrospectively examined the effect of vinpocetine infusion on various ophthalmological disorders. Based on the data of 280 patients they concluded that vinpocetine infusion has beneficial effects in numerous ophthalmologic disorders of vision and visual field. There was a clear difference regarding the response to treatment. Best results were achieved in diseases characterized by sclerosis, hypertonia and macular degeneration. The improvement was modest or progression was slowed in patients with nervus opticus ischaemia, glaucoma and myopia. These results are in accordance with the literature data. The beneficial effect of vinpocetine can be explained by the fact that the vessels of the eye are in direct connection with the cerebral circulation and hereby the circulation improving effect of vinpocetine could be effective. The neuronal effects of vinpocetine could also play a role at least in two ways. On the one hand by the direct effect exerted on the cells of retina (these cells are related to the neurons), and on the other hand by the improvement of the circulation and metabolism of the secondary visual cortex found in the occipital lobe (this effect is proved by PET studies).     

某院脑血管疾病患者30日内再入院影响因素分析

目的分析脑血管疾病患者30日内再入院影响因素,并针对性改进。方法采用描述性统计、卡方检验以及Logistic逐步回归分析法,探讨脑血管疾病患者30日内再入院的显著影响因素。结果脑卒中是30日内脑血管疾病复发再入院的最主要因素,占82.46%。年龄、性别、医保类型、是否手术、主诊断类型及有无并发症合并症是影响脑血管疾病30日内再入院的显著影响因素。其中,第一次入院主诊断为脑卒中及第一次入院合并高血压是影响脑血管疾病30日内再入院的两个危险因素。结论规范脑血管疾病临床路径,建立脑血管疾病早期预防筛查体系以及慢性病管理体系,可以降低脑血管疾病30日内再入院率。     

New approaches in neurosurgery and hyperbaric medicine--the importance of preventive and industrial medicine

Neurosurgical patients have been mainly treated by surgical procedures over the past decades. In addition, hyperbaric oxygen (HBO) therapy in neurosurgery has been used in patients with ischemic cerebrovascular diseases, head trauma, spinal damage, postoperative brain edema and others. However, the main therapeutic methods for neurosurgical diseases have changed dramatically due to developments in radiological techniques, such as radiosurgery and intravascular surgery. With changes in therapeutic methods, HBO therapy may become a very important treatment option for neurosurgical patients. For example, HBO therapy combined with radiotherapy (UOEH regimen) and anticoagulant therapy appear to be very effective in the treatments of malignant brain tumors and ischemic cerebrovascular diseases, respectively. On the other hand, medical examinations under hyper- and hypobaric environments have not yet been fully studied in the central nervous system compared to those in the cardiopulmonary systems. Moreover, the mechanisms of cerebral lesions in decompression sickness and acute mountain sickness remain unclear. Clinical neurologic approaches are very important in these fields. Hence, clinicians and researchers skilled in both neurosurgery and hyperbaric medicine will be required for advanced treatment and preventive and industrial medicine.     

Pathophysiological impact of cigarette smoke exposure on the cerebrovascular system with a focus on the blood-brain barrier: expanding the awareness of smoking toxicity in an underappreciated area

Recent evidence has indicated that active and passive cigarette smoking are associated, in a dose-dependent manner, with dysfunction of normal endothelial physiology. Tobacco smoke (TS) may predispose individuals to atherogenic and thrombotic problems, significantly increasing the risk for ischemic manifestations such as acute coronary syndrome and stroke. Despite the strong evidence for an association between smoking and vascular impairment, the impact of TS exposure on the blood-brain barrier (BBB) has only been marginally addressed. This is a major problem given that the BBB is crucial in the maintenance of brain homeostasis. Recent data have also shown that chronic smokers have a higher incidence of small vessel ischemic disease (SVID), a pathological condition characterized by leaky brain microvessels and loss of BBB integrity. In the brain TS increases the risk of silent cerebral infarction (SCI) and stroke owing to the pro-coagulant and atherogenic effects of smoking. In this article we provide a detailed review and analysis of current knowledge of the pathophysiology of tobacco smoke toxicity at the cerebrovascular levels. We also discuss the potential toxicity of recently marketed "potential-reduced exposure products".     

缺血性脑卒中不同期脑循环功能治疗仪疗效分析

目的：探讨缺血性脑卒中不同病期脑循环功能治疗仪对疾病功能康复、引发卒中因素及脑血流的影响。方法：将脑卒中患者分为治疗组和对照组,治疗组在常规药物治疗基础上加用脑循环功能治疗仪,对脑卒中不同病期的患者进行治疗。采用神经功能缺损评分、对卒中危险因素可控情况及TCDNi]定颈内动脉、椎动脉血流变化,评价治疗组和对照组脑循环功能治疗仪治疗的有效性、可行性。结果：不同脑卒中分期中治疗组经治疗后急性期神经功能缺损评分显著低于对照组（t=－13．26,P〈0．05）;且卒中引发因素血压、胆固醇水平较对照组下降显著（t=7．39,t=7．75,P〈0．05）,治疗组治疗后脑血流与对照组相比其在左、右颈内A和左、右椎动脉部分的Vd、Vs、Vm的血流量增加。结论：脑卒中在药物治疗的基础上加用脑循环功能治疗仪电刺激康复治疗更加便捷、经济、安全和有效,适用于脑卒中各期伴有高血压、胆固醇增高的患者。     

Stroke in chronic renal failure

Chronic kidney diseases and cardiovascular diseases have several common risk factors like hypertension and diabetes. In chronic renal disease stroke risk is several times higher than in the average population. The combination of classical risk factors and those characteristic of chronic kidney disease might explain this increased risk. Among acute cerebrovascular diseases intracerebral hemorrhages are more frequent than in those with normal kidney function. The outcome of stroke is worse in chronic kidney disease. The treatment of stroke (thrombolysis, antiplatelet and anticoagulant treatment, statins, etc.) is an area of clinical research in this patient group. There are no reliable data on the application of thrombolysis in acute stroke in patients with chronic renal disease. Aspirin might be administered. Carefulness, individual considerations and lower doses might be appropriate when using other treatments. The condition of the kidney as well as other associated diseases should be considered during administration of antihypertensive and lipid lowering medications.     

16排螺旋CT进行脑部灌注检查急性卒中的临床研究与操作配合

目的:探讨16排螺旋CT进行脑部灌注检查合理扫描参数在诊断中的意义。方法:应用灌注CT软件,通过创建脑血流量(CBF)、脑血容量(CBV)以及本地团注定时(峰值时间)图像,以图解方式说明灌注相关的参数(相对大脑血流量、相对脑部血容量、峰值时间)。由两名医生独立观察完成。结果:灌注CT结果表明检查潜在的缺血过程类型与范围的灵敏性和准确性能够分别达到90%和100%。结论:灌注CT可以辅助医生评估脑灌注分布的类型和范围。     

依达拉奉治疗脑血栓形成和脑栓塞的疗效观察

目的：比较依达拉奉治疗(Edaravone)脑血栓形成与脑栓塞的疗效差别。方法：对我院2004年1月-2004年10月收治的脑血栓形成和脑栓塞患者22例给予依达拉奉治疗。结果：治疗后患者的主要神经症状、日常生活能力均有改善，脑栓塞的神经功能缺损评分(ESS)和日常生活活动量表(ADL)评分较脑血栓形成高。结论：依达拉奉在治疗脑梗塞急性期中发挥着重要的作用，且脑栓塞的疗效优于脑血栓形成。     

Using a quality improvement process to create measurable improvement in care delivery for acute stroke

The introduction of thrombolytic therapy has revolutionized the management of acute ischemic stroke, and it has now been conclusively established that tissue plasminogen activator (t-PA) given within 4.5 hours of stroke onset both limits irreversible ischemic neuronal damage by establishing reperfusion of the penumbra and improves outcomes for patients who have undergone stroke. As a regional stroke centre, Hamilton Health Services (HHS) seeks to ensure it meets guidelines and readiness criteria in acute stroke care. This article discusses how HHS developed and used a quality improvement process to ensure all patients receive thrombosis therapy within 60 minutes of arrival at hospital.     

NCCT联合DSA对前循环急性缺血性脑卒中血管内介入治疗的评估价值

目的评估NCCT联合DSA对前循环急性缺血性脑卒中(CIS)血管内介入治疗的价值。方法 60例接受血管内介入治疗的前循环急性CIS患者均进行NCCT和DSA检查。分析诊断结果,并比较治疗前后的血管狭窄情况。结果 60例患者中,DSA检出60例阳性,NCCT检查显示41例阳性,19例阴性,准确度为68.33%。DSA检出9例血管正常,51例血管异常。43例大脑动脉闭塞以及狭窄患者治疗后的最小直径、病变长度显著高于治疗前,直径和面积狭窄程度显著低于治疗前(P<0.05)。结论 NCCT联合DSA可提高前循环急性CIS的诊断准确度,为血管内介入治疗提供重要依据,有利于改善血管狭窄,促进康复。     

奥扎格雷钠联合长春西汀治疗急性脑梗死的疗效观察

目的：观察奥扎格雷钠联合长春西汀治疗急性脑梗死的临床疗效。方法：84例急性脑梗死患者随机分为两组,对照组42例采用常规疗法,治疗组42例在常规治疗的同时加用奥扎格雷钠联合长春西汀,治疗前后比较两组患者神经功能缺损评分、临床疗效。结果：治疗后治疗组神经功能缺损评分明显降低,与对照组比较差异有统计学意义（P〈0．05）;治疗组总有效率为88．1％,高于对照组总有效率66．7％,比较差异有统计学意义（P〈0．05）。结论：奥扎格雷钠联合长春西汀治疗脑梗死疗效好,能明显改善患者临床疗效及预后。     

急慢性出血性脑卒中患者受损皮质脊髓束磁共振弥散张量成像特点分析

目的:探究急慢性出血性脑卒中患者受损皮质脊髓束磁共振成像(MRI)的弥散张量成像(DTI)特点分析.方法:选取60例出血性脑卒中患者,依据诊断结果将其分为急性出血性脑卒中组(急性组,21例)和慢性出血性脑卒中组(慢性组,39例).对两组患者进行DTI扫描,测量病变侧皮质脊髓束、病变对侧分数各向异性(FA)值及平均弥散率...