Ischemic stroke has the characteristics of high disability,high mortality,and high recurrence rate,and the abundant collateral circulation is an independent predictor of good outcomes in stroke.This article mainly elaborates the cytological and molecular mechanisms of vascular remodeling process after ischemic stroke in order to provide new ideas and targets for the treatment of ischemic stroke.

Objective To investigate the relationship between total cerebral small vessel disease (CSVD) burden and intracranial hemorrhage transformation (HT) after intravenous thrombolysis in patients with acute ischemic stroke (AIS).Methods One hundred and fifty-four patients who suffered from ischemic stroke within 4.5 hours of onset and received recombinant tissue plasminogen activator thrombolytic therapy in the emergency green channel of the First Affiliated Hospital of Soochow University from August 2016 to January 2018 were enrolled.HT examined by computed tomography scan within 24 hours after thrombolysis was included.The magnetic resonance imaging examination was performed within 48 hours.The patients were divided into two groups:HT group and control group according to the presence or absence of HT.Periventricular white-matter hyperintensities (WMH) with Fazekas score of 3 or deep WMH with Fasekas score of 2 or 3 was recorded as 1 point,MRI of cerebral microbleeds (CMBs) or lacunar infarction (LI) was recorded as 1 point respectively,and peripheral vascular space (PVS) in basal ganglia graded 2-4 (≥11)was counted 1 point.Single-factor analysis was used to compare total CSVD burden score,baseline data and clinical data between the two groups.Multivariate Logistic regression analysis was performed to explore the relationship between total CSVD burden score and HT.Results The age of the 154 patients was 66.00(59.00,74.25) years,males accounted for 66.9％ (103/154),onset to treatment time (OTT) was 174.50 (131.50,200.00) minutes and the NIHSS score before thrombolytic therapy was 6.00 (3.00,10.25).There were 43 cases (27.9％) with moderate to severe WMH,35 cases (22.7％) with CMBs,52 cases (33.8％) with PVS graded 2-4,and 96 cases (62.3％) with LI.There were 21 enrolled patients (13.6％) who suffered from HT.Symptomatic intracranial hemorrhage occurred in nine cases (5.8％).In the multivariate Logistic regression model,the results demonstrated that baseline diastolic pressure (OR=1.072,95％CI 1.027-1.118,P=0.001)and atrial fibrillation (OR=28.564,95％CI 6.217-131.241,P=0.000) were independently associated with HT.After using the mild CSVD burden score as a reference,moderate CSVD burden (OR=0.810,95％ CI 0.154-4.257,P=0.804) was not associated with HT after thrombolysis,and severe CSVD burden (OR=8.429,95％ CI 1.643-43.227,P=0.011) was independently associated with HT.Conclusions The severity of total CSVD burden in patients with AIS was closely related to HT after thrombolysis.Severe CSVD was an independent risk factor for HT after thrombolysis.

Objective: To describe bullying victimization of middle school students in Dalian and associated factors, so as to provide scientific basis for campus bullying prevention. Methods: The stratified cluster sampling method was used to select 2 540 middle school students from urban and rural areas in Dalian, who were investigated with campus bullying victimization and related factors. Results: The reported rate of campus bullying victimization among middle school students in Dalian was 25.11%. The rates of physical violence (5.99%, 3.66%) and verbal violence(24.93%, 15.87%) of male students were higher than that of female students( χ 2=6.56, 27.94, P <0.05). The rates of verbal violence (22.84%, 16.25%) and emotional neglect(16.84%, 13.18%) of junior high school students were higher than those of high school students( χ 2=14.21, 5.44, P < 0.05 ). The rates of physical violence(6.07%, 3.55%), verbal violence(24.58%, 16.05%) and emotional neglect(18.88%, 12.06 %) of rural students were higher than those of urban students( χ 2=7.72, 24.81, 19.64, P <0.05). Male students, junior high school students and rural students suffered more severe campus bullying than female students, high school students and urban students( Z =3.46, 3.75, 5.89, P <0.01). The structural equation model showed that academic performance (path coefficient -0.003) and father s education (path coefficient -0.004 ) have a direct negative effect on campus bullying behavior, while mother s education (indirect action coefficient -0.000 8), height(indirect action coefficient -0.000 3), father s education (indirect action coefficient -0.000 3) and weight (indirect action coefficient 0.000 2) indirect effects on campus bullying through academic performance. Conclusion The prevalence of campus bullying victimization among middle school students in Dalian is relatively high, which worths further attention to. Rural students, junior high school students and boys are more likely to suffer campus bullying. Improving academic performance might be beneficial for campus bullying prevention.

Objective　To evaluate the efficacy and safety of intravenous thrombolysis in acute mild ischemic stroke patients (National Institution of Health Stroke Scale≤5),moreover,to verify the effectiveness of multi-modality assessment in screening high-risk patients.Methods　We retrospectively included 227 patients identified with acute mild neurological deficits treated with or without intravenous thrombolysis.Odds ratios (OR) with their confidence intervals (CI) for different outcomes between groups were assessed by using multivariable binary logistic regression analyses.And the heterogeneity of treatment effect magnitude for excellent outcome［modified Rankin scale (mRS) 0~1 was estimated in different subgroups stratified by optimal cut-off value from receiver operating characteristic curve.Results　In multivariate analysis,intravenous thrombolysis could both achieve higher rate of excellent outcome(OR=3.302，95%CI1.488~7.326，P=0.003) and 7 day significant improvement (OR=2.566，95%CI1.287~5.118，P=0.007).However,there was no significant difference in the risk of early neurological deterioration,intracranial hemorrhage transformation or the 90 day stroke recurrence(P>0.05).It is indicated from the subgroup analysis that,compared with non-thrombolytic group,the classification of large artery atherosclerosis(OR=9.448，95%CI1.129~79.035，P=0.038) and baseline ABCD-2 score of 5 or more(OR=2.664，95%CI1.150~6.168，P=0.022) might benefit more from intravenous thrombolysis.Conclusion　For acute mild ischemic stroke patients,we reassured the safety and especially the efficacy of intravenous thrombolysis at 7 days and 90 days.Patients with ABCD-2 score of 5 or more and classification of large artery atherosclerosis might benefit more from intravenous thrombolytic therapy.

Objective To investigate the effects of magnesium sulfate and magnesium L-sulfonate on the neurobehavioral response and the expression of induced nitric oxide synthase (iNOS) in neurons after acute cerebral ischemia in rats. Methods One hundred and twelve male Sprague-Dawley ( SD) rats were double-blinded randomly divided into sham-operated group, middle cerebral artery occlusion ( MCAO ) group,MgSO4 treatment group,L-MgT treatment group. Each group was further divided into 6 h,12 h and 24 h subgroups according to the different detection time points. Rat MCAO models were produced following the Longa's method. And the Longa score,limb-placing test,rotarod test,and sticky tape test were performed to evaluate the neurological damage,autonomous movement and coordinate perception in the 24 h subgroup. At the end of the experiment,2,3,5-triphenyltetrazolium chloride ( TTC) was used to evaluate the area of cerebral infarction at 24 h reperfusion. Immunohistochemical staining was employed to determine the altera-tions in iNOS expression in neurons 6 h,12 h and 24 h after reperfusion. Results In behavioral evaluation:Longa score:Normal performance was observed in sham-operated group. Compared with the MCAO group,the scores of MgSO4 treatment group(1. 71±0. 18) and L-MgT treatment group(1. 14±0. 14) were decreased (t=0. 548,3. 873,all P<0. 05),and the score of L-MgT treatment group was lower than that of the MgSO4 group(t=2. 828,P<0. 05). Limb symmetry score:There was no statistically significant difference between MgSO4 group and MCAO group,but there was a statistically significant difference between L-MgT group and MCAO group (t=7. 071,P<0. 05). The roding experiment:The time of MgSO4 group and the L-MgT group were significantly different from that of the MCAO group (t=9. 588,20. 776,P<0. 05),and the time of the L-MgT group was significantly higher than that of the MgSO4 group (t=4. 983,P<0. 05). The right limb strip removal experiment: The time of MgSO4 group and L-MgT group were statistically different from that of MCAO group (t=6. 135,5. 825,P<0. 05),and the time of L-MgT group was increased compared with that of MgSO4 group(t=4. 507,P<0. 05). TTC test:No infarction was formed in the sham group. Compared with MCAO group ((36. 82±1. 35)%),the cerebral infarction volume of MgSO4 group ((17. 39±1. 72)%) and L-MgT group ((10. 81 ± 1. 35)%) significantly decreased, with statistically significant differences ( t=8. 874,11. 105,P<0. 05). Compared with MgSO4 group,cerebral infarction volume in L-MgT group was sig-nificantly reduced,with statistical significance (t=2. 593,P<0. 05). HE staining:There was no statistically significant difference in cell morphology between MgSO4 group and MCAO group at each time point,but the cell morphology of L-MgT group was intact compared with that of MCAO group. INOS staining at 24 h:There was no statistically significant difference in the positive cell density between the MgSO4 group and the MCAO group,but the L-MgT group (cortex:(196. 7±8. 1);striatum:(153. 3±3. 8)) positive cell density was lower than that of the MCAO group (cortex:(375. 0±6. 7),striatum:(358. 3±4. 5)),and the difference was sta-tistically significant (t=11. 113,36. 231,P<0. 05). Conclusion L-MgT may have a significantly protective effect on MCAO rats,and its mechanism may be related to the level of iNOS in neurons.

Objective: Symptomatic intracranial hemorrhage (sICH) is one of the severe complications of ischemic stroke thrombolysis. Several prognostic scales have been developed to predict the risk of sICH. The performance of seven scales was compared in a single center cohort. Methods: Data of patients with consecutive ischemic stroke who received 0.9 mg/kg intravenous recombinant tissue plasminogen activator (rt-PA) thrombolysis within 4.5 h time window from stroke onset were collected. Seven scales that can provide an estimate of risk of sICH were identified and evaluated: Hemorrhage After Thrombolysis (HAT), blood Sugar, Early infarct signs, (hyper) Dense cerebral artery sign, Age, National Institutes of Health (NIH) Stroke Scale (SEDAN), Stroke Prognostication using Age and NIH Stroke Scale (SPAN)-100, Safe Implementation of Thrombolysis in Stroke (SITS), Total Health Risks In Vascular Events (THRIVE), Glucose at presentation, Race (Asia), Age, Sex (male), systolic blood Pressure at presentation, and Severity of stroke at presentation (NIH Stroke Scale; GRASPS) and Multicenter Stroke Survey (MSS). The area under the receiver operating characteristic curve (AUROC) was calculated and Logistic regression and the Hosmer-Lemeshow test were also performed. Results: The current study included 293 patients, of whom 7.85% (23/293) had sICH by National Institute of Neurological Disorders and Stroke (SICH_NINDS), 5.46% (16/293) by Europe Cooperative Acute Stroke Study Ⅱ (SICH_ECASSⅡ) and 4.44% (13/293) by Safe Implementation of Thrombolysis in Stroke (SICH_SITS) criteria. SEDAN had the highest AUROC for predicting sICH: sICH_NINDS: AUROC=0.843, OR=3.167, 95%CI 2.106-4.762, P<0.01; sICH_ECASSⅡ: AUROC=0.797, OR=2.509, 95%CI 1.652-3.812, P<0.01; sICH_SITS: AUROC=0.784, OR=2.172, 95%CI 1.405-3.357, P<0.01. And SPAN-100 had the lowest AUROC among all the seven scales and was only associated with risk of SICH_NINDS in regression analysis. Furthermore, when sub-grouped the cohort into anterior circulation infarction and posterior circulation infarction, regression analysis suggested that all the seven scales were however not associated with sICH risk in patients with posterior circulation infarction. Conclusions SEDAN constantly had the highest predictive power, SPAN-100 had the worst. The seven scales studied could not predict sICH in posterior circulation infarction.