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Background and Purpose-Cerebral microbleeds (MBs) detected by gradient-echo MRI are considered evidence of advanced microangiopathy with potential for further bleeding. The goal of this study was to determine whether the presence of MBs is a risk factor for subsequent intracerebral hemorrhage among patients with acute ischemic stroke. Methods-We prospectively examined patients hospitalized with acute cerebral infarction with gradient-echo T2*-weighted MRI for the presence of MBs. We recorded demographics, medical history, and stroke severity. Patients were then followed up for the development of stroke, other vascular events, and death. Results-One hundred twenty-one consecutive patients with a mean age of 67.96Ϯ10.97 years were recruited. MBs were present in 43 patients (35.5%). During follow-up of 27.15Ϯ11.68 months, 16 patients had recurrent stroke. There was no difference between patients with or without MB for the development of ischemic stroke (5 and 6 respectively, Pϭ0.841). However, 4 patients (9.3%) with MBs and 1 patient (1.3%) without an MB had intracerebral hemorrhage during follow-up (Pϭ0.053). Of the 5 patients who developed subsequent intracerebral hemorrhages, 3 were treated with aspirin and 2 with anticoagulation. Two of the intracerebral hemorrhages occurred in the site where asymptomatic MBs were found at baseline. Conclusions-MBs appear to be a risk factor for subsequent intracerebral hemorrhage among patients with ischemic stroke in this small cohort of Chinese stroke patients. A large cohort study is required to confirm this observation.

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Risk and mortality of ICH increased with quantity of MB. As tendency to recurrent CI exceed that of ICH, anti-thrombotic agents are still warranted. However, in patients with >or= 5 MB, the high risk and mortality of ICH seem to outweigh the modest benefit of antithrombotic agents. Extra precautions should be taken to minimize risk of ICH. Further studies in patients on Coumadin and assessment of functional outcome are warranted to support these preliminary findings.

Background: Intracranial artery calcification is common but the prevalence and determinants are not well established. We aim to describe the prevalence and location of calcification in intracranial arteries according to brain multi-detector-row computed tomography (MDCT) images, and to investigate its correlation with potential risk factors. Methods: We studied consecutive men and women referred for brain CT in December 2004. All patients received a questionnaire regarding their medical history related to atherosclerosis, including traditional risk factors of atherosclerosis, serum chemistry values and inflammatory markers. All CT examinations were done with a 16-slice MDCT and the severity of intracranial artery calcification was categorized. Results: Four hundred and ninety patients aged 1.4–101 years (62.92 ± 19.04; mean ± SD) were included in our study. There were 340 patients (69.4%) who had intracranial artery calcification. The highest prevalence of intracranial artery calcification was seen in the internal carotid artery (60%), followed by vertebral artery (20%), middle cerebral artery (5%) and basilar artery (5%). Patients with calcification were significantly older than those without calcification (p < 0.001). A significantly higher prevalence of calcification was present among patients with hypertension (p < 0.001), diabetes (p < 0.001), renal failure (p < 0.05), atrial fibrillation (p < 0.05), smoking (p < 0.05), hyperlipidemia (p < 0.001), ischemic heart disease (p < 0.05) and ischemic stroke (p < 0.001). Mean values of serum phosphate, serum urea and CRP level were also significantly higher in patients with intracranial artery calcification (p < 0.05, respectively), and there was a trend that patients with intracranial calcification had a higher white blood cell count (p = 0.070). Stepwise multiple logistic regression showed age (RR = 2.795 per 10 years), a history of ischemic stroke (RR = 3.915), and white blood cell count (RR = 1.107) to be independently associated with intracranial artery calcification. Conclusions: Calcification of the intracranial arteries is associated with age, history of ischemic stroke and white blood cell count. Further prospective studies to investigate the clinical significance of intracranial artery calcification are needed.

Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine.

Trace Zn(2+) and Cu(2+) in living cells play important roles in the regulation of biological function. It is significant to simultaneously detect the cellular Zn(2+) and Cu(2+). Here, we present a novel two-color fluorescence nanoprobe based on the DNAzymes for simultaneous imaging of Zn(2+) and Cu(2+) in living cells. The probe consists of a 13 nm gold nanoparticle, DNAzymes that are specific for Zn(2+) and Cu(2+), and the substrate strands labeled with fluorophores at the 5' end and quenchers at the 3' end. The fluorescence of the fluoreophores is quenched both by the gold nanoparticle and the quencher. After the nanoprobes are transferred into the cells, the substrate strands would be cleaved in the presence of the Zn(2+) and Cu(2+) target, resulting in disassociation of the shorter DNA fragments containing fluorophores, which produce fluorescence signals correlated with the location and concentration of the Zn(2+) and Cu(2+). The nanoprobe exhibits high specificity, nuclease stability, and good biocompatibility. Moreover, the nanoprobe can simultaneously monitor the cellular Zn(2+) and Cu(2+) with an on-site manner, providing the information on localization and concentration of targets, which is significant to further research the Zn(2+)- and Cu(2+)-relative cellular events and biological process. The proposed method has shown great potential in the detection of multiple metal ions in living cells, which may help us to better understand the function of metal ions in the fields of biochemistry, molecular biology, and cellular toxicology.

Multiple acute cerebral infarcts (MACIs) detected by diffusion-weighted imaging (DWI) may indicate an unstable source of thromboembolism. The authors studied 119 consecutive acute ischemic stroke patients within 24 hours of onset with DWI. MACIs were present in 20 patients (16.8%). During the follow-up period, there were 15 recurrent strokes, 3 acute coronary syndromes, and 5 deaths. MACI was the only significant independent predictor for vascular events and death (odd ratio [OR]] = 4.34; p = 0.001) and stroke recurrence (OR = 5.93; p = 0.001).