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Five kinds of graphene nanoplatelet-modified explosive lead styphnate composites (GLS) have been synthesized with different GNPs content from 0.1 to 2.0 mass% and characterized by SEM, XRD and Raman spectra. The initial thermal decomposition behaviours were studied by DPTA, and the complete thermal decompositions were studied by DSC and TG for the everlasting thermal stability of explosives in storage and application. The effects of GNP contents on thermal decomposition were investigated. The evolved gas amount from DPTA test indicates that GLS 1.0 % has the best thermal stability at ambient storage conditions. According to TG and DSC tests, the characteristic temperatures of thermal decomposition ( T and T), the thermodynamic parameters (Δ S, Δ H and Δ G), the kinetic parameters ( E and A) also confirmed this view. The results indicate that the GNP plays two opposite roles in their thermal decomposition processes, the catalysis reaction and hindering thermal conduction. [ABSTRACT FROM AUTHOR]

Introduction: To evaluate the effects of the multiple burr hole (MBH) revascularization on ischemic type adult Moyamoya disease (MMD) by computed tomography perfusion (CTP). Methods: Eighty-six ischemic MMD patients received CTP 1 week before and 3 weeks after MBH operation. Fifty-seven patients received it again at 6 month and underwent digital subtraction angiography (DSA) and mRS follow-up. Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and relative values of ischemic symptomatic hemispheres were measured. Differences in pre- and post-surgery perfusion CT values were assessed. Results: There were significant differences of CBF, TTP, and relative time to peak (rTTP) in ischemic hemisphere between 1 week before and 3 weeks after surgery, and no significant difference in relative cerebral blood flow (rCBF), CBV, relative cerebral blood volume (rCBV), MTT, relative mean transit time (rMTT). According to whether there was symptom improvement or not on 3 weeks after MBH, the rTTP value was not statistically significant in the patients whose symptoms were not improved at all on 3 weeks after operation. Six-month follow-up showed that CBF, rCBF, and rCBV values were significantly higher than those before operation. Postoperative MTT, TTP, rMTT, and rTTP values were significantly lower than those before operation. Conclusion: CTP is a sensitive method to obtain functional imaging of cerebral microcirculation, which can be a noninvasive assessment of the abnormalities of intracranial arteries and cerebral perfusion changes in MMD before and after surgery. CBF and TTP map, especially the relative values of TTP, seems to have the capability of being quite sensitive to the presence of altered brain perfusion at early time after indirect revascularization. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated that hyperglycemia may result in a poor prognosis following aneurysmal subarachnoid hemorrhage (aSAH). However, the association between hyperglycemia and the clinical outcome of aSAH has not been clearly established thus far. Therefore, we performed a systematic review and meta-analysis to investigate the association between hyperglycemia and the development of aSAH. We completed a literature search in four databases (PubMed, EMBASE, Cochrane Library, and Web of Science) up to November 1, 2021, including all eligible studies investigating the prognostic value of hyperglycemia in patients with aSAH. We performed a quality assessment of included studies using the Newcastle–Ottawa Quality Assessment Scale. The pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated to assess the association of hyperglycemia in aneurysmal subarachnoid hemorrhage. A total of 35 studies with 11,519 patients were finally included in the meta-analysis. Nineteen studies reported the association between hyperglycemia and poor outcome, 12 studies reported the association between hyperglycemia and all-cause mortality, 7 studies reported the association between hyperglycemia and cerebral vasospasm, and 9 studies reported the association between hyperglycemia and cerebral infarction. The pooled data of these studies suggested that hyperglycemia was significantly associated with poor functional outcomes (odds ratio [OR], 1.29; 95% confidence interval [CI], 1.17–1.42; P < 0.00001; I2 = 83%), all-cause mortality (OR, 1.02; 95% CI, 1.01–1.04; P = 0.0006; I2 = 89%), cerebral vasospasm (OR, 1.02; 95% CI, 1.01–1.02; P = 0.0002; I2 = 35%), and cerebral infarction (OR, 1.16; 95% CI, 1.09–1.23; P < 0.00001; I2 = 10%) in aSAH patients. These findings suggested that assessing for hyperglycemia at admission may help clinicians to identify critically ill patients and complete patient stratification early, which may achieve better management and improve the prognosis of patients with aSAH. [ABSTRACT FROM AUTHOR]

Objectives: We performed this study to report our experience using a stepwise stent deployment technique for the treatment of tandem intracranial aneurysms.Methods: Patients with intracranial tandem aneurysms that were treated with a stepwise stent deployment technique between May 2009 and June 2013 were retrospectively reviewed.Results: Twenty-one patients with 42 tandem aneurysms were identified (11 men, 10 women), with a mean age of 53.7 years (range, 17-82 years). Subarachnoid haemorrhage was confirmed in 12 patients using computed tomography at onset. Complete occlusion was achieved in 20 of the aneurysms (47.6%) after the procedure, neck remnant in 9 (21.4%), and aneurysm remnant in 13 (31.0%). The perioperative complications included in-stent thrombosis in one case and vasospasm in two cases, none of which left a permanent neurological deficit. The modified Rankin Scale (mRS) score at discharge was 0-2 in 20 cases and 3 in one case. The follow-up angiograms available for 17 patients showed complete occlusion in 26 aneurysms, improved in 4, and stable in 4. All of the patients had mRS scores of 0-1 during the clinical follow-up period.Conclusions: The stepwise stent deployment technique is feasible and helpful in the treatment of intracranial tandem aneurysms.Key Points: • Treating wide-necked intracranial aneurysms with stent-assisted coiling is preferable. • Tandem wide-necked intracranial aneurysms can be treated with a single stent. • Stepwise stent deployment is technically feasible for embolizing tandem intracranial aneurysms. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to evaluate risk factors of sis-VADAs recurrence after reconstructive treatment based on 113 reconstructed lesions. Methods: A total of 111 patients (M:F = 68:43; median age, 47 years) with 113 sis-VADAs underwent reconstruction from October 2000 to March 2011, using stent(s) and coils. Treatments and predictors of recurrence were retrospectively analysed. Results: Fifty-eight sis-VADAs underwent single-stent treatment, and the remaining 55 sis-VADAs underwent treatment with 2-4 overlapping stents. Follow-up angiography was available for 94 sis-VADAs 12 -78 months, with recurrence in ten patients, including seven angiographic recurrences and three post-treatment haemorrhagic recurrences. A higher rate of post-treatment recurrence was observed in the single stent group than in the multiple stents group ( p = 0.010). The interaction between stent (s) implantation and immediate occlusion degree (odds ratio [OR] =3.152; 95 % confidence interval [CI], 1.293-7.686; p = 0.012), between stent (s) implantation and the posterior inferior cerebellar artery (PICA) involvement (OR = 4.607; 95 % CI, 1.172-18.113; p = 0.029), and between PICA involvement and immediate occlusion degree (OR = 5.018; 95 % CI, 1.263-19.933; p = 0.022) affect recurrence in the reconstructed sis-VADAs. Conclusions: This single centre cohort study indicated that the interaction effect between stent (s) implantation, PICA involvement, and immediate occlusion degree were closely associated with recurrence after reconstructive treatment of sis-VADA. Key Points: • The interaction between stent (s) and immediate occlusion degree affect aneurysmal recurrence • The interaction between stent and PICA involvement affect aneurysmal recurrence • The interaction between PICA involvement and immediate occlusion degree affect aneurysmal recurrence [ABSTRACT FROM AUTHOR]

Circulating endothelial progenitor cells (EPCs) play a critical role in maintaining endothelial integrity and keeping vascular homeostasis. Previously, we reported that EPCs were involved in repair and remodeling of aneurismal wall. In the present study, we verified this hypothesis by investigating the proliferative ability and count of EPCs in peripheral blood of patients with unruptured intracranial aneurysms (UIAs). Twenty-four patients with UIAs (UIA group) and 24 negative controls (control group) were included in this study. Peripheral blood monocytes (PBMCs) were harvested and selectively cultured. The colony-forming ability of cultured cells was analyzed and the biological functions were examined by testing the adsorption of ulex europaeus agglutinin-1 labeled by fluorescein isothiocyanate and acetylated low-density lipoprotein internalization. The migratory and adhesive ability of cultured EPCs were assessed. In vitro cultured PBMCs were identified as EPCs by examining surface markers CD34, CD133 and vascular endothelial growth factor receptor 2 using flow cytometry. EPCs from UIA group possessed significantly decreased proliferative, migratory and adhesive capacities compared with EPCs from control group. Furthermore, EPCs count in UIA group was significantly decreased. Collectively, these results indicated that the circulating EPCs of UIA patients may be involved in intracranial aneurysm repair and remodeling. [ABSTRACT FROM AUTHOR]

Background: Saccular aneurysms located at the M1 segment of the middle cerebral artery (MCA) are uncommon, and endovascular treatment (EVT) for them is not well documented. We performed this study to evaluate the feasibility, safety, and efficacy of EVT for proximal (M1) segment saccular aneurysm of the middle cerebral artery. Methods: Of 153 MCA aneurysms between January 2007 and September 2011, 29 patients with 29 M1 segment saccular aneurysms were treated at our institution via endovascular approach. There were 14 men and 15 women with a mean age of 56.2 years (range 36-78 years). Results: Treatments were successful in 28 (96.6 %) cases, including coiling alone in 19 patients, stent-assisted coiling in 8, and balloon-assisted coiling in 1. In the failed case, coiling was not successful, and only a stent was deployed. Immediate angiograms showed total occlusion in 13 patients, neck remnant in 7, partial occlusion in 8, and contrast stasis in the patient who was not coiled successfully. Two (6.9 %) procedure-related complications occurred, including early temporal branch (ETB) obliteration in one patient and lenticulostriate artery (LSA) occlusion in the other one, which resulted in hemiparalysis of one patient. Three patients died from initial severe SAH during hospitalization. One patient died from heart infarction 1 month after operation. Twenty-three of 25 surviving patients underwent follow-up cerebral angiography at intervals ranging from 1 to 21 months (mean, 7.3 months). The result showed 14/23 (60.9 %) aneurysms were completely occluded, 3/23 (13 %) were recanalized, and others were stable or improved. The clinical follow-up (mean, 22.5 months) of all survived patients demonstrated no neurologic deterioration or rebleeding. Conclusion: Our preliminary experience demonstrates that EVT for proximal MCA aneurysm is feasible and safe. However, more adequate follow-up is required to evaluate its long-term results. [ABSTRACT FROM AUTHOR]