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1.
OBJECTIVE: The objectives of this study were to investigate the prevalence of extracranial carotid plaque and the association between risk factors and carotid plaque in Japanese patients with ischemic stroke. METHODS: We consecutively recruited patients with ischemic stroke admitted to our hospital from January 2000 to September 2002. Neurologic signs and a brain magnetic resonance imaging diagnosed ischemic stroke. All subjects underwent a carotid ultrasonography. Multiple logistic regression analysis was used to determine the risk factors that independently contributed to the presence of carotid plaques. RESULTS: Carotid plaques were identified in 76.2% of the patients and bilateral plaques were found in 58.2%. These lesions were more frequent in comparison with previous Japanese reports. The risk factors that independently contributed to the presence of extracranial carotid plaques were hypertension, age, smoking and past history of ischemic stroke. CONCLUSIONS: This study demonstrates that extracranial carotid plaque is increasing in Japanese patients with ischemic stroke.  相似文献   
2.
OBJECTIVES: To obtain data on long-term mortality among young ischemic stroke patients compared with controls in this population-based study. MaTERIAL AND METHODS: We used Kaplan-Meier survival analysis to compare 232 patients aged 15-49 years with first-ever cerebral infarction in 1988-1997 and 453 controls followed from inclusion to death or 1 August 2005 for 2515 and 5558 person-years respectively. In a subanalysis of 192 patients, we compared risk factor variables using the Kaplan-Meier method and log-rank testing. We applied a Cox proportional hazards model to adjust for multiple risk factors. RESULTS: Forty-five patients and nine controls died during follow-up (P < 0.0005). Independent risk factors for mortality were active tumor disease (P < 0.0005), high consumption of alcohol (P < 0.0005), coronary atherosclerosis (P < 0.001), living alone (P < 0.02), seizures (P < 0.04) and smoking (P = 0.08). CONCLUSIONS: Long-term mortality was significantly increased among young stroke patients, mainly due to such lifestyle factors as high consumption of alcohol and tobacco.  相似文献   
3.
The present study assessed whether chlorogenic acid (CGA), a phenylpropanoid molecule that has multiple mechanisms of action would be useful to attenuate behavioral deficits associated with embolic strokes using the rabbit small clot embolic stroke model (RSCEM). Quantal analysis for each treatment determines the quantity of microclots (mg) that produce neurologic dysfunction in 50% of a group of animals (P(50)), with intervention considered beneficial if it increases the P(50) compared to controls. CGA (50 mg/kg) injected 5 min post-embolization significantly increased behavioral function and the P(50) to 3.61+/-0.52 mg (n=19) compared to 1.58+/-0.15 mg (n=26) in controls. In addition, CGA also increased the P(50) to 2.57+/-0.28 mg (n=18) when administered 1 h post-embolization, but was ineffective when given 3 h following embolization (P(50)=1.22+/-0.24 mg, n=18). For combination studies with the thrombolytic tissue plasminogen activator (tPA), we used tPA at a standard dose of 3.3 mg/kg, which significantly increased the P(50) to 2.89+/-0.29 mg (n=17) when administered 1 h after embolization, but not 3 h after embolization (P(50)=1.54+/-0.27 mg, n=18). However, when tPA (3.3 mg/kg) was combined with CGA (50 mg/kg) and administered 3 h following embolization, there was a significant increase in behavioral function as evidenced by an increase in the P(50) value to 3.40+/-0.76 mg (n=23). In conclusion, as a mono-therapy CGA effectively reduced behavioral deficits when given up to 1 h following embolic strokes in rabbits. Moreover, there was a synergistic effect of the combination of tPA with CGA when administered 3 h following embolization. The results show that the therapeutic window for a standard effective dose of tPA could be increased by administration of CGA, suggesting that it may be most useful as a co-therapy with a standard thrombolytic treatment regimen.  相似文献   
4.
Plasma levels of brain natriuretic peptide (BNP) are frequently elevated after an acute stroke and have been shown to be an independent predictor of mortality. However, the relationships between stroke and BNP concentrations have not yet been systematically investigated. Plasma BNP assay and echocardiography were performed in 48 patients with ischemic stroke or TIA with a mean delay of 12.7 h after onset. Median BNP concentration was 88.6 pg/mL (range 5–1270). Older age, chronic heart failure, atrial fibrillation, stroke severity, lower hemoglobin levels, lower left ventricular ejection fraction, and abnormalities of left atrium or appendage (LA/LAA) were univariately associated with increased BNP levels. At multivariable analysis, the presence of at least one LA/LAA abnormality (atrial dilatation, low flow velocity, spontaneous echocontrast or thrombus) had the strongest association with BNP, explaining 38.9% of the variance in the whole sample and 28.5% in patients without atrial fibrillation. In acute ischemic stroke patients, elevated plasma BNP levels have multiple determinants, among which left atrial disease appears to be the stronger, even in patients without atrial fibrillation. These results encourage further investigation of plasma BNP concentration as a potential marker of the presence of left atrial sources of emboli.  相似文献   
5.
The site of vascular stenosis correlates well with the Oxfordshire Community Stroke Project (OCSP) classification among Caucasians, but not among ethnic Chinese patients. We prospectively studied 205 consecutive ethnic South Asian ischemic stroke patients to investigate the prevalence of intracranial large artery disease determined by transcranial color-coded doppler and magnetic resonance angiography among OCSP subtypes. The distribution of OCSP subtypes was 7% total anterior circulation infarction (TACI), 17% partial anterior circulation infarction (PACI), 14% posterior circulation infarction (POCI) and 62% lacunar infarction (LACI). Significant intracranial large artery disease was common among all OCSP subtypes; 79% with TACI, 47% PACI, 65% POCI and 44% LACI. This is similar to ethnic Chinese data and is likely due to the predominance of intracranial disease over extracranial disease. Clinical axioms using OSCP subtypes based on Caucasian data may be misleading if applied to ethnic South Asians.  相似文献   
6.
Summary Phospholipase A2 (E.C. 3.1.1.4, PLA2) plays an essential role in metabolism of membrane phospholipids, it is related to inflammatory reactions, secretion of amyloid precursor protein and activation of NMDA receptor after ischemia. In the present study we investigated PLA2 activity in platelets from 37 Alzheimer’s disease (AD) patients, 32 vascular dementia (VaD) patients and 32 individuals with ischemic stroke as compared to 27 healthy elderly controls. PLA2 activity was determined using radiometric assay. Mean platelet PLA2 activity was increased in individuals with Alzheimer’s disease (p < 0.001). In VaD group the enzyme activity was between the values in AD and controls, these differences being significant from both groups. In the group of patients with ischemic stroke mean PLA2 activity was higher either 48 h after the stroke or 7 days later (in both cases p < 0.001). The results may be particularly interesting in light of the fact, that inhibitors of PLA2 activity are known.  相似文献   
7.
Objective to evaluate the influence of clustering of vascular risk factors (VRF) on in-hospital mortality in patients with acute ischemic stroke (AIS) developing a risk score for mortality prediction. Methods clinical data from 1527 patients admitted to hospital with a first-ever AIS were prospectively evaluated from 1997 to 2005 assessing the presence of six VRF: diabetes, hypertension, hyperlipidemia, ischemic heart disease, atrial fibrillation and peripheral arterial disease. A composite vascular risk score (VRS) was created using five risk factors.Hyperlipidemia was excluded from the score due to its protective impact on mortality. Two modified VRS models were created and assessed for their accuracy as predictors for in-hospital mortality based on the odds ratio for each VRF obtained in the univariate analysis. Results 197 patients (12.9 %) died during the acute hospitalization period. Stroke severity increased with each additional VRF (p = 0.002). Cox proportional hazards model adjusted for confounders showed an association between the composite VRS and in-hospital mortality (p = 0.045). According to the clustering of VRS, the risk for in-hospital death increased from 1.951 (95 % CI 1.041–3.665) for patients having one VRS to 2.343 (95% CI 1.081–5.076) for those having a VRS ≥ 4. ROC curves showed that the modified VRS model based on a given value of one for each accumulated VRF, including the absence of hyperlipidemia, had the highest predictive capability for in-hospital mortality (p < 0.0001). Conclusions the presence of multiple VRF in patients with acute ischemic stroke increases the stroke severity and the risk of in-hospital death.  相似文献   
8.
Abstract Objective To determine independent clinical predictors of stroke-associated pneumonia (SAP) that are available in all patients on day of hospital admission. Methods We studied 236 patients with acute ischemic stroke admitted to the neurological intensive care unit at our university hospital. Risk factors of SAP and of non-responsivity of early-onset pneumonia (EOP; onset within 72 hours after admission) to initial antibacterial treatment were analyzed. Results Incidence of SAP was 22%. The following independent risk factors were found to predict SAP with 76% (EOP: 90%) sensitivity and 88% specificity: dysphagia (RR, 9.92; 95% CI, 5.28-18.7), National Institute of Health Stroke Scale ≥ 10 (RR, 6.57; CI, 3.36-12.9), non-lacunar basal-ganglia infarction (RR, 3.10; CI, 1.17-5.62), and any other infection present on admission (RR, 3.78; CI, 2.45-5.83). Excluding the patients with other infections on admission, the same independent risk factors (except infection) were found. Further, but not independent risk factors were: combined brainstem and cerebellar infarction, infarction affecting more than 66% of middle cerebral artery territory, hemispheric infarction exceeding middle cerebral artery territory, impaired vigilance, mechanical ventilation, age ≥ 73 years, current malignoma, and cardioembolic stroke, whereas patients with lacunar infarctions had significantly lower risk. In contrast to previous reports, no impact of male gender or diabetes was found. Initial vomiting, especially if associated with impaired vigilance, predicted antibacterial treatment non-responsivity of EOP. In nonresponders exclusively fungal pathogens were identified. Conclusion Increased risk of pneumonia in acute stroke patients can be sufficiently predicted by a small set of clinical risk factors.  相似文献   
9.
Background and purpose Stratification of patients with transient ischemic attack (TIA) or ischemic stroke (IS) by risk of recurrent stroke can contribute to optimized secondary prevention. We therefore aimed to assess cardiovascular risk factor profiles of consecutive patients hospitalized with TIA/IS to stratify the risk of recurrent stroke according to the Essen Stroke Risk Score (ESRS) and of future cardiovascular events according to the ankle brachial index (ABI) as a marker of generalized atherosclerosis Methods In this cross-sectional observational study, 85 neurological stroke units throughout Germany documented cardiovascular risk factor profiles of 10 consecutive TIA/IS patients on standardized questionnaires. Screening for PAD was done with Doppler ultrasonography to calculate the ABI. Results A total of 852 patients (57% men) with a mean age of 67±12.4 years were included of whom 82.9 % had IS. The median National Institutes of Health stroke sum score was 4 (TIA: 1). Arterial hypertension was reported in 71%, diabetes mellitus in 26%, clinical PAD in 10%, and an ABI ≤ 0.9 in 51%. An ESRS ≥ 3 was observed in 58%, which in two previous retrospective analyses corresponded to a recurrent stroke risk of ≥ 4%/year. The correlation between the ESRS and the ABI was low (r = 0.21). Conclusion A high proportion of patients had asymptomatic atherosclerotic disease and a considerable risk of recurrent stroke according to the ABI and ESRS category. The prognostic accuracy as well as the potential benefit of various risk stratification scores in secondary stroke prevention require validation in a larger prospective study.  相似文献   
10.
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