In this paper (Cell 95[6], 829-837), we described the direction of the nodal cilia rotation as counterclockwise (Figure 6B). However, our recent analyses with higher spatiotemporal resolution revealed that the actual direction is clockwise when seen from the ventral side (above the nodal pit cells). In our previous observation with lower temporal resolution (10 frames per second), the direction of the rapid rotation 01ف( rounds per second) of the nodal cilia was misinterpreted due to the artifact caused by the strobe effect. It should be noted that this artifact only affects the apparent direction of the rotary movement. Thus, the direction of the linear movement of the beads in the extraembryonic fluid or the direction of the nodal flow is leftward albeit the low temporal resolution of our previous analysis. Therefore, the clockwise rotation of the nodal cilia causes the leftward nodal flow. For further details, refer to our recent paper Y. Okada et al. (Molecular Cell, 1999, in press).
Background and Purpose-About one half of those who develop adult-onset moyamoya disease experience intracranial hemorrhage. Despite the extremely high frequency of rebleeding attacks and poor prognosis, measures to prevent rebleeding have not been established. The purpose of this study is to determine whether extracranial-intracranial bypass can reduce incidence of rebleeding and improve patient prognosis. Methods-This study was a multicentered, prospective, randomized, controlled trial conducted by 22 institutes in Japan.Adult patients with moyamoya disease who had experienced intracranial hemorrhage within the preceding year were given either conservative care or bilateral extracranial-intracranial direct bypass and were observed for 5 years. Primary and secondary end points were defined as all adverse events and rebleeding attacks, respectively. Results-Eighty patients were enrolled (surgical, 42; nonsurgical, 38). Adverse events causing significant morbidity were observed in 6 patients in the surgical group (14.3%) and 13 patients in the nonsurgical group (34.2%). Kaplan-Meier survival analysis revealed significant differences between the 2 groups (3.2%/y versus 8.2%/y; P=0.048). The hazard ratio of the surgical group calculated by Cox regression analysis was 0.391 (95% confidence interval, 0.148-1.029).Rebleeding attacks were observed in 5 patients in the surgical group (11.9%) and 12 in the nonsurgical group (31.6%), significantly different in the Kaplan-Meier survival analysis (2.7%/y versus 7.6%/y; P=0.042). The hazard ratio of the surgical group was 0.355 (95% confidence interval, 0.125-1.009). Conclusions-Although statistically marginal, Kaplan-Meier analysis revealed the significant difference between surgical and nonsurgical group, suggesting the preventive effect of direct bypass against rebleeding. Clinical Trial Registration
The significant parallel losses of three basal lamina components, both in number and intensity, contribute to loss of microvascular integrity. These phenomena may be important for understanding cell extravasation and the hemorrhagic consequences of acute stroke.
Background and Purpose Polymorphonuclear leukocytes have been implicated in the development of the "no-reflow" phenomenon after focal cerebral ischemia and reperfusion. To further understand the role of granulocytes in microvascular occlusions, the responses of the granulocyte-endothelial cell adhesion molecules P-selectin and intercellular adhesion molecule-1 during middle cerebral artery ischemia and reperfusion were examined in a primate model.Methods Twelve adolescent male baboons were used for 2-hour middle cerebral artery occlusion (n=3) or for 3-hour occlusion with 1-hour (n=3), 4-hour (n=3), and 24-hour (n=3) reperfusion, and three separate unoperated primates served as controls. A quantitative immunohistochemical study of the microvascular distribution of P-selectin and intercellular adhesion molecule-1 was performed using 10-/j.m frozen sections from basal ganglia analyzed with computerized light microscopy video imaging.
Hemorrhagic transformation after cerebral ischemia is a well known clinical concern. The frequency of intact basal lamina (BL), identified by laminin antigen, in hemorrhagic and nonhemorrhagic zones after middle cerebral artery occlusion (MCA:O) and 3-h MCA:O with reperfusion in adolescent male baboons was assessed. Parenchymal hemoglobin was not detected prior to 24-h reperfusion. A significant decrease in the density of laminin (BL) in hemorrhagic zones (6.2 +/- 2.4) compared with nonhemorrhagic ischemic zones (10.5 +/- 2.4) (p < 0.05) and nonischemic basal ganglia (17.0 +/- 2.7) (p < 0.01) was observed. Time-dependent changes in BL integrity appear linked to the extravasation of blood components.
SummaryBackgroundIntracerebral haemorrhage growth is associated with poor clinical outcome and is a therapeutic target for improving outcome. We aimed to determine the absolute risk and predictors of intracerebral haemorrhage growth, develop and validate prediction models, and evaluate the added value of CT angiography.MethodsIn a systematic review of OVID MEDLINE—with additional hand-searching of relevant studies' bibliographies— from Jan 1, 1970, to Dec 31, 2015, we identified observational cohorts and randomised trials with repeat scanning protocols that included at least ten patients with acute intracerebral haemorrhage. We sought individual patient-level data from corresponding authors for patients aged 18 years or older with data available from brain imaging initially done 0·5–24 h and repeated fewer than 6 days after symptom onset, who had baseline intracerebral haemorrhage volume of less than 150 mL, and did not undergo acute treatment that might reduce intracerebral haemorrhage volume. We estimated the absolute risk and predictors of the primary outcome of intracerebral haemorrhage growth (defined as >6 mL increase in intracerebral haemorrhage volume on repeat imaging) using multivariable logistic regression models in development and validation cohorts in four subgroups of patients, using a hierarchical approach: patients not taking anticoagulant therapy at intracerebral haemorrhage onset (who constituted the largest subgroup), patients taking anticoagulant therapy at intracerebral haemorrhage onset, patients from cohorts that included at least some patients taking anticoagulant therapy at intracerebral haemorrhage onset, and patients for whom both information about anticoagulant therapy at intracerebral haemorrhage onset and spot sign on acute CT angiography were known.FindingsOf 4191 studies identified, 77 were eligible for inclusion. Overall, 36 (47%) cohorts provided data on 5435 eligible patients. 5076 of these patients were not taking anticoagulant therapy at symptom onset (median age 67 years, IQR 56–76), of whom 1009 (20%) had intracerebral haemorrhage growth. Multivariable models of patients with data on antiplatelet therapy use, data on anticoagulant therapy use, and assessment of CT angiography spot sign at symptom onset showed that time from symptom onset to baseline imaging (odds ratio 0·50, 95% CI 0·36–0·70; p<0·0001), intracerebral haemorrhage volume on baseline imaging (7·18, 4·46–11·60; p<0·0001), antiplatelet use (1·68, 1·06–2·66; p=0·026), and anticoagulant use (3·48, 1·96–6·16; p<0·0001) were independent predictors of intracerebral haemorrhage growth (C-index 0·78, 95% CI 0·75–0·82). Addition of CT angiography spot sign (odds ratio 4·46, 95% CI 2·95–6·75; p<0·0001) to the model increased the C-index by 0·05 (95% CI 0·03–0·07).InterpretationIn this large patient-level meta-analysis, models using four or five predictors had acceptable to good discrimination. These models could inform the location and frequency of observations on patients in clinical practice, explain treatment effects i...
Antiplatelet therapy seems to contribute to the acute clinical deterioration of intracerebral hemorrhage.
Background and Purpose Ischemic cerebral injury is associated with activation of the blood coagulation cascade. To elucidate the contribution of fibrin formation to microvascular injury during focal cerebral ischemia and reperfusion, we have studied the time course and the localization of fibrin deposition in cerebral microvessels and the surrounding tissues during ischemia/reperfusion in a well-described nonhuman primate model.Methods Cerebral tissues from adolescent male baboons were examined after 2-hour middle cerebral artery occlusion (n=3) and after 3 hours of middle cerebral artery occlusion and 1-hour (n=6), 4-hour (n=3), and 24-hour (n=4) reperfusion; tissues from control primates (n=3) also were examined. Fibrin deposition was detected by immunohistochemical techniques using the fibrin-specific monoclonal antibody MH-1. The number and size distribution of microvessels associated with fibrin were quantified by video-imaging microscopy.Results Fibrin was associated with microvessels only in the ischemic zone where severe neuronal injury was documented,
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