Research progress of circadian rhythm and reperfusion therapy in wake-up stroke / 中华神经科杂志

Wake-up stroke (WUS) is clinically defined as ischemic stroke that is associated with neurological deficits on awakening,accounting for approximately one in five individuals presenting with an acute ischemic stroke.At present,the mechanism of WUS onset is still unclear,and whether circadian mechanisms are involved deserves further exploration.Previously,these patients were missed the opportunity of reperfusion therapy due to unknown onset time.Recent studies have changed this concept.Intravenous thrombolysis or mechanical thrombectomy can be performed in appropriate patients after imaging evaluation,thus improving the prognosis of some patients with WUS.This article summarizes the latest research in recent years.

Research progress of circadian rhythm and reperfusion therapy in wake-up stroke / 中华神经科杂志

Wake-up stroke (WUS) is clinically defined as ischemic stroke that is associated with neurological deficits on awakening, accounting for approximately one in five individuals presenting with an acute ischemic stroke. At present, the mechanism of WUS onset is still unclear, and whether circadian mechanisms are involved deserves further exploration. Previously, these patients were missed the opportunity of reperfusion therapy due to unknown onset time. Recent studies have changed this concept. Intravenous thrombolysis or mechanical thrombectomy can be performed in appropriate patients after imaging evaluation, thus improving the prognosis of some patients with WUS. This article summarizes the latest research in recent years.

To analyse the rate of intraplaque hemorrhage in symptomatic vertebral artery stenosis by high-resolution MRI / 实用医学杂志

Objective To compare the rate of intraplaque hemorrhage between symptomatic and asymptom-atic vertebral artery stenosis groups using high-resolution magnetic resonance imaging(HR-MRI).Methods The patients diagnosed with PCI and with vertebral artery stenosis using HR-MRI were enrolled retrospectively. They were divided into symptomatic and asymptomatic groups according to whether they were detected with PCI by the re-sponsible vertebral artery stenosis before examination. All patients underwent 3D time of flight magnetic resonance angiography(3D TOF MRA)to detect the stenosis location of vertebral artery and the stenosis rate at the narrow-est. T1-weighted fat-suppressed images were positioned on the atherosclerotic plaque that the signal 150% higher than the surrounding muscle was confirmed to be intraplaque hemorrhage. Statistical significance was assessed by chi-square test or Student′s unpaired t test.Results A total of 60 patients were included in this study,28 patients in the symptomatic group and 32 patients in the asymptomatic group.The rate of vertebral artery stenosis in asymp-tomatic group was higher than symptomatic group,but there was no statistical significance[(72 ± 33)% vs.(65 ± 28)%,P=0.383];the number of intraplaque hemorrhage in symptomatic group was significantly higher than that in the asymptomatic group(9 vs.2,P=0.024).Conclusions There is a higher rate of intraplaque hemorrhage in symptomatic vertebral artery stenosis group than asymptomatic group.Intraplaque Hemorrhage could be one of risk factor of acute ischemic cerebral disease.

Analysis of relevant factors to the outcomes of spontaneous intracerebral hemorrhage in young adults / 中华急诊医学杂志

Objective To study factors used to predict 30-day mortality and favorable outcomes to intracerebral hemorrhage (ICH) in young adult subjects and to estimate the reliability of these predictors.Methods Data of 175 acute ICH patients selected from 201 patients admitted to our hospital from 2008 to 2011 were reviewed retrospectively.Patients were assessed with Glasgow Coma Scale (GCS) and National Institutes of Health Stroke Scale (NIHSS) and routine laboratory examinations after admission.Independent predictors of 30-day mortality or good outcome (modified Rankin score,0-2) were identified by stepwise logistic regression.Results There were 90 male and 85 female,and 142 survivals and 33 deaths.The modified Rankin score (mRS) of survival group was ＜6 and mRS =6 in death group,and mRS ＜3 in good outcome group and mRS ＞ or =3 in poor outcome group.Independent factors for 30-day mortality were hypertension (P =0.023) or hyperglycemia (P =0.007),infra-tentorial ICH (P =0.000),large ICH volume (P =0.008),low Glasgow Coma Scale (GCS) scores (P =0.000),high white blood cell count (P =0.000),higher blood glucose level (P =0.039) and prothrombin time (PT) (P =0.001) after admission.Independent factors for 30-day good outcome were younger age (P =0.001),normal blood pressure (P=0.010) or absence of hyperglycemia (P=0.028),lower NIHSS scores (P=0.000),small ICH volume (P =0.000),low white blood cell (WBC) count (P =0.000),lower blood glucose level (P =0.012) or lower systolic blood pressure (SBP) level (P =0.000) at admission.The NIHSS score and GCS score were excellent predictors,while the SBP level,WBC count and ICH volume were fine predictors.Conclusions Overall prognostic factors should be integrated to get high reliabilities for predicting the outcomes of ICH in young people.

Protective effect of DL-3-n-Butylphthalide on radiation injury of rat brain tissue / 中华放射医学与防护杂志

Objective To investigate the protective effect and its mechanism of DL-3-n-Butylphthalide on the brain damage in rats following whole brain irradiation.Methods A total of 120 male Sprague Dawley rats were randomly divided into sham-irradiation group,irradiatien group and DL-3-n-Butylphthalide group.The model of whole-brain irradiatien was established by exposuring rat brain to 4 MeV X-rays with a single-dose of 10 Gy.The rats were intraperitoneally injected with DL-3-n-Butylphthalide at the dosages of 0.3,1.0,and 3.0 mg/kg once a day.The contents of malondialdchyde and super oxide dismutase activity were measured,while the expressions of apoptosis-associated genes and the ultrastructural changes in hippocampus were examined by immunohistnchemisty staining and electron microscope,respectively.Results After irradiation,the content of malondialdehyde and the expression of apoptosis gene bax in rat brain tissue increased while the activity of super oxide dismutase(SOD) and the expression of anti-apoptosis gene bcl-2 decreased.Apoptosis was also observed in the neurons of hippocampus CA1.Compared with irradiation group,the content of malondialdehyde and the expression of bax gene in the DL-3-n-Butylphthalide group wen significantly reduced ( t =-3.89--1.96,2.72-3.48,P ＜ 0.05 ),while the activity of SOD and bcl-2 gene were significantly elevated ( t =2.94-3.76,-3.18--2.08,P ＜ 0.05),and the injury degree of neuron structure in the DL-3-n-Butylphthalide group was slighter than that in the irradiation group.Conclusions DL-3-n-Butylphthalide executes protective effects in a dose-dependent manner againest the radiation injury in rats brain by reducing the induction of malondialdehyde,raising the activity of SOD and inhibiting the generation of apoptosis.

Effects of 1-3-n-Butylphthalide on the blood-brain barrier following whole brain irradiation in rats / 中华放射肿瘤学杂志

ObjectiveTo investigate the effects of 1-3-n-Butylphthalide on the blood-brain barrier (BBB) following whole brain irradiation in rats.Methods144 male Sprague Dawley rats were randomly divided into sham-irradiation group,irradiation group,1-3-n-Butylphthalide group,and irradiation plus 1-3-n-Butylphthalide group.Whole-brain irradiation was given as a single-dose of 10 Gy using 4 MV X-ray.The rats were injected intraperitoneally with 1-3-n-Butylphthalide at 0.3 mg/kg,1.0 mg/kg,3.0 mg/kg once per day.The changes of the BBB were assessed by Evans blue (EB) assay.The expression of vascular endothelial growth factor (VEGF) in the brain tissue was determined by immunohistochemistry. The circulating endothelial cells (CECs) isolated from right ventricular blood were counted.MRI was evaluated with the T1-weighted images,T2-weighted images and MRI enhancement images induced by Gd-DTPA.The data were compared among the groups through Student-Newman-Keuls test.ResultsCompared with the sham-irradiation group,the EB content,the expression of VEGF in the brain tissue and the CECs were significantly increased in the irradiation group (2.81∶ 7.82,P =0.002;5.83∶ 10.26,P=0.003;3.16∶6.14,P =0.002).The signal intensity of T1-weighted images was significantly decreased while T2-weighted images and the enhancement rate significantly increased in the irradiation group (P =0.004 -0.018 ).Compared with irradiation group,the EB content,the expression of VEGF and the CECs were decreased significantly in the irradiation plus 1-3-n-Butylphthalide group ( 7.80∶ 3.86,P =0.007 ; 10.83 ∶ 5.26,P =0.008 ;6.36∶ 3.64,P =0.009 ).However,the changes in the MRI were significantly attenuated ( P =0.008-0.026,and 0.006 -0.038,respectively).Conclusions Following whole brain irradiation,1-3-n-Butylphthalide can decrease the permeability of the BBB in rats via decreasing VEGF expression and decreasing the CECs.

MicroRNAs and neuronal apoptosis after cerebral ischemia / 国际脑血管病杂志

MicroRNAs (miRNAs) are a class of highly conserved non-coding small RNA molecules.They regulate gene expression by inhibiting transcription or translation.Ischemic stroke is one of the major diseases of resulting in death and disability worldwide.The final outcome of its pathological process is neuronal death.Neuronal apoptosis is mainly seen in ischemic penumbra,and saving the neurons in penumbra are the key to the treatment of ischemic stroke.This article reviews the roles of miRNAs in the neuronal apoptosis during cerebral ischemia.

Anticoagulant therapy in prevention and treatment of ischemic stroke / 国际脑血管病杂志

The activation of coagulation system,especially in the occurrence and development of cardiogenic cerebral embolism,plays an important role.As one of the major preventive measures in ischemic stroke,the anticoagulant therapy is getting more and more attention.At the same time,the studies of anticoagulant drugs aiming to the intervention of different links in coagulation pathway have also made significant progress.

Advances on the research of carbon nanotubes in the field of dental biomaterials / 国际生物医学工程杂志

Because of their unique neno-structures and outstanding mechanical,thermodynamic,and magnetic properties,carbon nanotubes have attracted intensive interests in the field of stomatology,especially in the research of composite materials,such as toughened ceramic,reinforced polymethyl methacrylate,etc.In this paper,the current and prospective applications of carbon nanotubes in stomatology were reviewed.Also some comments were made on the existing problems and prospects of the relative research were discussed.