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Vascular mild cognitive impairment (VMCI) is an early and reversible stage of dementia. Volume differences in regional gray matter may reveal the development and prognosis of VMCI. This study selected 2 of the most common types of VMCI, namely, periventricular white matter hyperintensities (PWMH, n = 14) and strategic single infarctions (SSI, n = 10), and used the voxel-based morphometry method to quantify their morphological characteristics. Meanwhile, age- and sex-matched healthy volunteers were included (n = 16). All the participants were neuropsychologically tested to characterize their cognitive function and underwent whole-brain magnetic resonance imaging scanning. Our results showed that the volumes of the bilateral temporal lobes and bilateral frontal gray matter were obviously diminished in the PWMH group. The atrophy volume difference was 4,086 voxels in the left temporal lobe, 4,154 voxels in the right temporal lobe, 1,718 voxels in the left frontal lobe, and 1,141 voxels in the right frontal lobe (P ≤ 0.001). Moreover, the characteristics of the gray matter atrophy associated with the PWMH were more similar to those associated with Alzheimer’s disease than SSI, which further revealed the susceptibility for escalation from PWMH to dementia. In conclusion, PWMH patients and SSI patients have different morphological characteristics, which explain the different prognoses of VMCI.

Optimal treatment strategies for traumatic intracranial internal carotid artery (ICA) pseudoaneurysms are controversial. The low-profile visualized intraluminal support (LVIS) device is a braided stent with a metal coverage rate between traditional laser cut stents and flow diversion devices. We report here our therapy strategy using the LVIS stent-assisted coiling for treatment of traumatic intracranial ICA pseudoaneurysms. Patients with traumatic intracranial ICA pseudoaneurysms treated by the LVIS stent-assisted coiling in our center between January 2015 and June 2021 were reviewed. The complications, radiographic, and clinical outcomes of these patients were analyzed. A total of 12 patients with 12 pseudoaneurysms were included. The mean maximum aneurysm diameter was 6.2 ± 3.1 mm. Nine patients had a subarachnoid hemorrhage; five patients with Hunt-Hess grade III and four patients with grade IV. All procedures were successfully performed without intraoperative complications. Immediate postoperative angiogram showed that six (50%) aneurysms were Raymond grade 1, four (33.3%) were grade 2, and two (16.7%) were grade 3. Postoperative multiple cerebral infarction occurred in two patients because of vasospasm. Of the ten patients with angiographic follow-up (mean, 29.9 months), two received additional coiling because of recanalization of the pseudoaneurysm, and all aneurysms were completely obliterated at the last examination of the patients. During the clinical follow-up period (mean, 26.8 months), the overall mortality and morbidity were 25% (3/12) and 8.3% (1/12), respectively. LVIS stent-assisted coiling was a feasible approach for the treatment of traumatic ICA pseudoaneurysms.

The reliable and dynamic detection of amyloid β-protein (Aβ) deposition using imaging technology is necessary for preclinical Alzheimer's disease (AD), which may significantly improve prognosis. The present study aimed to evaluate the feasibility of applying angiopep-2 (ANG), a chemical exchange saturation transfer-magnetic resonance imaging (CEST-MRI) biomarker, for monitoring Aβ deposition in vivo. ANG exerted a good chemical exchange saturation transfer (CEST) effect and displayed a moderate binding affinity to Aβ1-42 in vitro. Six-month-old mice with AD injected with ANG exhibited a significantly enhanced CEST effect than controls in vivo; this effect gradually became more apparent at 8, 10, and 12 months. Spatial learning impairment caused by abundant Aβ deposition (representing mild cognitive impairment in AD patients) develops at 12 months in APPswe/PSEN1dE9 (line 85) AD mice. To conclude, the CEST of ANG could display very earlier age-related Aβ pathological progress in mice with AD, consistent with immunohistochemistry. ANG has extraordinary potential for clinical transformation as an imaging biomarker to diagnose early AD and track its progress dynamically and nonradiationally.

Few studies have examined the postoperative hemorrhage rate of cerebral arteriovenous malformations (AVMs) treated by embolization prior to stereotactic radiosurgery. The objective of this analysis was to compare the postoperative hemorrhage rate between AVMs treated with and those treated without preradiosurgery embolization. A systematic search of the PubMed and Embase databases was performed with no restriction on the publication period. Based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies with sufficient baseline and outcome data. The analysis was performed using Comprehensive Meta-Analysis (CMA) 2.0. Eleven studies comprising 2591 patients were eligible for analysis. There was no significant difference in the postoperative hemorrhage rate between patients who had undergone embolization followed by SRS and those who had undergone SRS alone (OR 1.140, 95% CI 0.851-1.526, p = 0.38). The obliteration rate was significantly lower in the E + SRS group than in the SRS group (OR 0.586, 95% CI 0.398-0.863, p = 0.007). No significant difference in permanent neurological deficits was identified between patients who had undergone embolization followed by SRS and those who had undergone SRS alone (OR 1.175, 95% CI 0.626-2.206, p = 0.616). Available data suggested that preradiosurgery embolization did not reduce the postoperative hemorrhage rate and resulted in a significantly lower obliteration rate than treatment with SRS alone.

The safety and benefit of mechanical thrombectomy (MT) in the treatment of acute ischemic stroke (AIS) patients with M2 segment middle cerebral artery occlusions remain uncertain.To investigate the benefit of mechanical thrombectomy for M2 occlusion compared with M1 occlusion in patients with AIS.The PubMed, Embase, and Cochrane Library databases were searched from inception to April 2021 to identify relevant articles. The main results comprised 90-day functional independence (modified Rankin Score from 0-2), successful recanalization (thrombectomy in cerebral infarction [TICI] 2b/3), mortality, and rates of symptomatic intracerebral hemorrhage after using modern thrombectomy devices. Odds ratios (ORs) were generated for binary variants. ReviewManager 5.3 software was used.Ultimately, a total of 14 trials were included, with 3454 participants enrolled. MT for M2 occlusion had a higher rate of 3-month functional independence than M1 occlusion, but the difference was nonsignificant (OR: 1.19, 95% confidence interval [CI]: 0.98 to 1.46). The TICI2b/3 scores (OR: 0.71, 95% CI: 0.58-0.88) in M2 occlusion were remarkably lower than those in M1. The mortality and symptomatic intracerebral hemorrhage rates were comparable between the 2 groups. When comparing M2 and M1 occlusions, we found that there was no significant difference between stent retriever and aspiration in the modified Rankin Score (0-2) after AIS, but aspiration exerted an eminently higher recanalization rate with regard to TICI2b/3 (OR: 0.77, 95% CI: 0.61-0.96).Compared with M1 occlusion, patients with M2 occlusion treated by MT demonstrated similar clinical outcomes in this study. Moreover, there was no difference between stent retriever and aspiration in treating M2 occlusion in terms of functional independence at 90 days. However, aspiration exerted a conspicuously higher recanalization rate in M2 occlusion than in M1 occlusion.

Early life stress (ELS) is associated with an increased risk of developing depression and anxiety disorders. Disturbances of the neurobiological glutamatergic system are implicated in depression; however, the long-term effects of ELS on glutamate (Glu) metabolites remain unclear. Our study used 7T proton magnetic resonance spectroscopy (7T 1H MRS) to detect metabolic Glu in a rat model to investigate maternal deprivation (MD)-induced ELS. MD was established in Sprague-Dawley rats by periodic separation from mothers and peers. Changes in the hippocampal volume and Glu metabolism were detected by 7T 1H MRS after testing for depression-like behavior via open field, sucrose preference, and Morris water maze tests. Adult MD offspring exhibited depression-like behavior. Compared to the control, the MD group exhibited reduced ratio of central activity time to total time and decreased sucrose consumption (p < 0.05). MD rats spent less time in the fourth quadrant, where the platform was originally placed, in the Morris water maze test. According to 7T 1H MRS, hippocampus of MD rats had elevated Glu and glutamate + glutamine (Glu+Gln) levels compared with the control group hippocampi, but Gln, γ-aminobutyric acid (GABA), and glutamate + glutamine (Glu+Gln) in the prefrontal cortex of MD rats showed a downward trend. Depression-like behavior and cognition deficits related to ELS may induce region-specific changes in Glu metabolism in the prefrontal cortex and hippocampus. The novel, noninvasive 7T 1H MRS-identified associations between Glu levels and ELS may guide future clinical studies.

The need for energy is growing as civilization develops. Superconductors have various benefits over regular conductors, including a high current-carrying density and nearly no resistance. Therefore, the objective that scientists continue to seek is the use of superconductors to replace traditional conductors in order to satisfy the demand for energy. As a key part of the superconducting electrical system, the critical current is one of the key properties of high-temperature superconducting (HTS) coils. Scholars have created a variety of numerical simulation models to estimate the performance of HTS coils. However, the extremely nonlinear E–J power law relationship that characterizes the voltage–current relationship in superconducting materials necessitates numerous iterative refinements during the coil design stage, which is time-consuming from the perspective of computing efficiency. Consequently, it is essential to increase computational efficiency. In this study, the critical current of HTS coils was calculated using the J model (integral method with the current density J as the state solution variable), and it was proved to be an efficient research method. The accuracy of the method is verified by comparing with the H model and the experimental measurement results of the critical current of the HTS coil. Moreover, compared with the reference finite element simulation model, this model has a speed advantage of at least four times, which is a good choice, especially, for HTS circular coils with large turns.

Inductance is a very commonly used electrical parameter in transient progress analysis, as well as in energy storage evaluations. It was normally considered as constant when the geometrical configuration of a coil is determined. However, experiments on Bi-2223 (Bi 2 Sr 2 Ca 2 Cu 3 O 10+x ) and YBCO (YBa 2 Cu 4 O 7-x ) coils, both show 10% rise inductance while increasing the applied current. The inductance grows approximately a linear relationship from its minimum to maximum. We used both theoretical and experimental analysis to deeply understand the mechanism of the variation in terms of current distribution in high-temperature superconducting (HTS) coils. Taking this inductance change into account would benefit the accuracy in energy storage applications and in transient analysis occasions. Besides, inductance controllable devices could be achieved by manipulating the bias current applied on HTS coils.

Until recently, a new type of open magnetic shielding system was realized by the combination of a series of closed high temperature superconductor coils. We experimentally confirmed that the shielding factor (SF) of the new shielding system can reach more than 40 dB in the frequency spectrum of 0.1–16 000 Hz. Because of its superior ability to resist alternating magnetic field, we named, the system Tesla-shielding (TS), to commemorate the father of alternating current, Nikola Tesla. In this paper, we will report the design and realization of a Helmholtz coil-based TS. The Helmholtz TS has many advantages over the previous planar TS. Especially, the Helmholtz TS has an engineering way of regulating the device for a better SF. We will introduce the design of the Helmholtz TS with the help of numerical simulation. The main electromagnetic properties of the TS, such as SF in the frequency spectrum and its shielding ability in the long duration measurement, are given in this paper.

In this paper, the I c degradation of bent YBCO tapes has been experimentally studied. The I c characteristics in length direction was measured through a non-contact, continuous I c measurement equipment (Mcorder), which is suitable for all kinds of high temperature superconducting (HTS) tapes. The detailed J c mapping of bent tapes was investigated by a Hall microscopy equipment (Mcorder 2-D), which scans the fields distribution on the surface of the films or bulks. A 4.1-m-long YBCO tape was wound on a 4.5-mm-diameter core with YBCO face outside or inside. The critical current of the YBCO tape before and after winding was measured lengthwise. And the 2-D J c map of the samples of degraded sections was measured. The result shows that the smallest safe bending diameter is larger than 14 mm and smaller than 4.5 mm, for YBCO face outside and inside, respectively, which indicates that the YBCO face is recommended to be inside in bending cases. The relation between critical current of YBCO face outside bent tapes and diameters was fitted to a sigmoid-like function, to help further development where YBCO face outside bending is unavoidable.

Background and Purpose: Although endovascular treatment (EVT) for acute ischemic stroke is classified as I evidence, outcomes after EVT in real-world practice appear to be less superior than those in randomized clinical trials (RCTs). Additionally, the effect of EVT is unclear compared with medical treatment (MT) for patients with mild symptoms defined by National Institutes of Health Stroke Scale score Methods: Literatures were searched in big databases and major meetings from December 6, 2009, to December 6, 2019, including RCTs and observational studies comparing EVT against MT for patients with acute ischemic stroke. Observational studies were precategorized into 3 groups based on imaging data on admission: mild stroke group with National Institutes of Health Stroke Scale score Results: Fifteen RCTs (n=3694) and 37 observational studies (n=9090) were included. EVT was associated with higher modified Rankin Scale 0 to 2 rate and lower mortality in RCTs and normal stroke group, whereas EVT was associated with higher sICH rate in normal stroke group, and no difference of sICH rate appeared between EVT and MT in RCTs. In severe stroke group, EVT was associated with higher modified Rankin Scale 0 to 2 rate and lower mortality, whereas no difference of sICH rate was found. In mild stroke group, there was no difference in modified Rankin Scale 0 to 2 rate between EVT and MT, whereas EVT was associated with higher mortality and sICH rate. Conclusions: Evidence from RCTs and observational studies supports the use of EVT as the first-line choice for eligible patients corresponding to the latest guideline. For patients with Alberta Stroke Program Early CT Score

BackgroundThe current diagnosis of Parkinson's disease (PD) is mainly based on the typical clinical manifestations. However, 60% dopaminergic neurons have died when the typical clinical manifestations occur. Predictive neurobiomarkers may help identify those PD patients having non-motor disorders or in different stage and achieving the aim of early diagnosis. Up to date, few if any neuroimaging techniques have been described useful for non-movement disorders diagnosis in PD patients. Here, we investigated the alteration of metabolites in PD patients in different stage of PD and non-motor symptoms including sleep, gastrointestinal and cognitive dysfunction, by using the 1H-MRS.MethodsA total of 48 subjects were included between 2017 and 2019: 37 PD (15 men, age 47–82 years) and 11 healthy people (8 men, age 49–74 years). All participants underwent MRI and multi-voxel 1H-MRS examination within 3 days in admission. Six kinds of metabolites, such as creatine (Cr), N-acetyl aspartate/creatine (NAA/Cr), N-acetyl aspartate/choline (NAA/Cho), choline/creatine (Cho/Cr), lipid/creatine (LL/Cr), and myo-Inositol/creatine ratio (mI/Cr) were tested among the PD group and the control groups. Statistical analyses and correlation analyses were performed by using SPSS. The p < 0.05 was considered statistically significant.ResultsCompared late PD group with a control group or early group, higher Cr ratio and lower NAA/Cr ratio were observed in the late PD group (p < 0.05). The mI/Cr in the late PD group was also lower than that in the early PD group (p < 0.05). Regarding the relationship between metabolites and NMS, Cho/Cr was higher in the sleep disorder group, whereas mI/Cr was lower in the gastrointestinal dysfunction group in comparison with the non-symptom groups. Moreover, Cr, Cho/Cr, mI/Cr, and LL/Cr were identified to have higher concentrations in the cognitive group in thalamus.ConclusionsProton magnetic resonance spectroscopy is an advanced tool to quantify the metabolic changes in PD. Three biomarkers (Cr, NAA/Cr, and mI/Cr) were detected in the late stage of PD, suggesting that these markers might be potential to imply the progression of PD. In addition, subgroups analysis showed that MRS of thalamus is a sensitive region for the detection of cognitive decline in PD, and the alteration of neurochemicals (involving Cr, Cho, mI, and LL) may be promising biomarkers to predict cognitive decline in PD.

Endovascular treatment (EVT) is merely recommended as class of recommendation IIb for patients with ASPECTS6 according to the American Heart Association guideline 2019. In addition, the best determined imaging technique for EVT in patient with ASPECTS6 remains unknown. The objective of this study was to define the safety and efficacy of EVT for patients with ASPECTS6 and investigate the superiority between MRI and CT for patient selection.A systematic search of PubMed, EMBASE, The Cochrane Library and other additional sources was performed for studies published with no publication period. Our study was conducted corresponding to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRIMA) guidelines. The analysis was performed using the Comprehensive Meta-Analysis (CMA) 2.0.Five studies reporting data from 844 participants were included in our analysis according to the inclusion criteria. Consequently, EVT was associated with statistically significant higher functional independence compared with MT (OR 5.401, 95% CI 3.227-9.041). Whereas EVT was found to be related to lower mortality compared with MT based on eligible data (OR 0.461, 95% CI 0.329-0.647). No significant difference was identified in sICH between EVT and MT (OR 1.075, 95% CI 0.452-2.558).According to the results of our study, we suggested that EVT is a preferred therapy in ACS patients with ASPECTS6 in consideration of efficacy and safety. Furthermore, MRI did not show superiority over CT as no statistical difference was detected in all subgroups.

Flux penetration and AC loss are among the key problems in the application of high-temperature superconductors (HTSs). Through simulation, the value and distribution of AC loss in HTS equipment can be evaluated and optimized in the design stage, so as to ensure the reliability and stability of the equipment. At present, there are many algorithms for AC loss calculation that can be simplified to a two-dimensional model, but for the case of three-dimensional structure such as cable in a spiral structure, there are still some problems such as difficult meshing, difficult convergence, and low efficiency. In this paper, an upgrade of the two-dimensional J model to a three-dimensional J model is proposed, permitting effective calculation of the flux penetration and AC loss in the CORC cable. The reliability of the method is verified by comparing the calculated results with the analytic model and with experimental results. At present, this method can efficiently calculate a 3D CORC model with a total of 15 superconducting tapes in five layers. Also discussed is the feasibility of upgrading to calculate larger models.

Since there is no iron core and the energy is only coupled through the primary and secondary windings, air-core transformers have advantages of no iron loss, no magnetic saturation, and compact in size, which make them attractive to be studied for practical applications. Due to its high current density and low loss, high temperature superconductor (HTS) brings additional advantages for this type of transformer. The HTS wires are highly magnetic field dependent and their characteristics are required for the HTS implementation and the design of the air-core transformers. As a result, magnetic field distribution of the HTS windings is researched, and its influence on the HTS critical currents, ac loss, and the transforming efficiency of the HTS air-core are analyzed.

The formation and interfacial property of complex coacervates were characterized based on CMC and gelatin with different Bloom values (140, 180, 200, 220, and 240). Gelatins with higher Bloom values had more α-chains and β-chains as well as more triple-helix structures. The turbidity curve and optimal pH point for electrostatic neutralization between CMC and gelatin were dependent on the Bloom value. The complex coacervate with medium Bloom values (200) and mass ratio (gelatin/CMC 9:1) showed higher yield (87.56%) and more uniform spherical microstructure, which was correlated with appropriate binding sites and steric hindrance of gelatin. The existence of gelatin with the lower Bloom value enhanced the emulsifying activity of complex coacervates by decreasing the interfacial tension to 16.4 mN/m. However, higher Bloom value was beneficial to the emulsifying stability of the complex coacervates with the ESI up to 21.3 min. With the increasing of molecular weight, the stability of the coacervate exhibited an increasing trend for the higher thickness of the interface film. When used gelatin (200, Bloom value) for microencapsulating cinnamaldehyde, the thermal stability improved significantly and core material uniformly released compared with unencapsulated cinnamaldehyde.

Stem bending during vase time is a major problem in many cultivars of cut gerbera flowers. In this study, we focused on the involvement of postharvest bacteria and evaluated the efficacy of nano-silver (NS) in reducing bacterial proliferation and stem bending in cut gerbera ‘Real’ flowers in vitro and in vivo. Four species of dominant bacteria, Pseudomonas sp., Acinetobacter junii, Bacillus stearothermophilus, and Myroides sp., were isolated from the stem ends of cut gerberas. Exogenous addition of 3–5 log10 colony forming units (CFU) mL−1 of each bacterial species resulted in a sharp reduction in vase life, relative fresh weight, and water uptake of cut gerbera flowers. However, Pseudomonas sp. had little impact on their vase life and ornamental quality at concentrations of 3–4 log10 CFU mL−1. In vitro assessments showed that the minimum inhibitory concentrations (MICs) of NS for both A. junii and Myroides sp. were 2.5 mg L−1, and NS MICs for B. stearothermophilus and Pseudomonas sp. were 5 and 7.5 mg L−1, respectively. Additionally, compared with the control, pretreatment with 5 and 10 mg L−1 NS for 24 h nearly doubled the vase life of cut gerberas, maintained their relative fresh weight, and improved water uptake. Furthermore, scanning electron microscopy revealed that the NS pretreatment reduced bacterial colonization on the stem ends. Overall, our findings indicate that all four genera of dominant bacterial species isolated from the stem ends of cut gerberas are involved in stem bending, and NS pretreatment effectively alleviated bacteria-induced xylem blockage and improved water uptake, thereby reducing the incidence of stem bending and extending the vase life of cut gerberas.

The complexation mechanism of gelatin (G) and carboxymethyl cellulose (CMC) and their coacervates formation process were studied as a function of pH and protein (Pr) to polysaccharide (Ps) mixing ratio (Pr:Ps). Three different CMCs were chosen (FL9, FH9 and FVH6) and five mixing ratio of 1:1, 6:1, 7:1, 8:1 and 9:1 (w/w), were studied to disclose their individual coacervates transition pattern for zeta potential, turbidity, morphology, size distribution and coacervates yield. The coacervates formation mechanism and stability of formed coacervates were examined using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR), Circular Dichroism (CD), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Coacervates with better morphology, good size distribution and highest yield were observed with G-FL9 at mixing ratio of 7:1 and pH 4.40. The evaluation of coacervates formation mechanism showed that G molecules experienced a conformational change in its secondary structure from a flexible pattern to an ordered poly-proline II (PPII) helix. The vibrations of O H and N H bonds spectra at 3437 and 3449 cm −1 , respectively for G/CMC coacervates, shifted to lower wave numbers due to the conformational changes of gelatin and CMC, during the coacervates formation. G/CMC complex coacervates were more thermally stable than individual gelatin. Therefore, these complex coacervates will be able to protect and deliver heat sensitive bioactives and food ingredients.

Most HTS (high-temperature superconductor) coils will quench due to defects in the winding. Some of these defects come from tape manufacturing, but more commonly are generated in the process of making a coil, especially for the YBCO racetrack coils that use epoxy resin to solidify the winding. In order to find out defects, chemical solutions are used to dissolve epoxy resin of three damaged YBCO racetrack coils. YBCO tapes reclaimed from these coils are scanned by MCorder, a continuous critical current measurement device that can tell amplitude of defects and distribution of defects in a high speed and high resolution. The scan result shows severe defects everywhere in the winding. However, during the solidification process, outer turns are more vulnerable to the defects than the inner turns. We believe that the delamination of YBCO tape caused by contraction of the epoxy resin contributes to the defects.

Reducing heat leakage is crucial for the development of practical superconducting devices. In this work, orthogonal experimental design method is first used to optimize the design of hundred-ampere and kiloampere Peltier current leads (PCLs). Geometry and arrangement of Peltier materials and conductive materials of the current lead are analyzed. Through our simulation, we find that the coupling effect between the radius of Bi2Te3 (r2) and the length of Bi2Te3 (L2) has the greatest effect on the heat leakage of PCLs at the cold end for both PCLs. Furthermore, numerical simulations suggest that the lowest heat leakage at the cold end (approximately 30.0 W/kA) is at the same level for both hundred-ampere and kiloampere PCLs. If taking the heat dissipation area at the hot end into account, multiterminal solutions are better solutions for kiloampere current leads.

Objective Because the formation of associated aneurysms (AAs) related to the characteristics of cerebral artriovenous malformations (cAVMs) is poorly recognized, the purpose of this study was to identify the responsible characteristics of cAVMs related to the formation of AAs and to identify patients with responsible characteristics related to the formation of AAs through the analysis of the outcomes of these patients after treatment. Methods This study was performed to analyze the baseline characteristics of patients with cAVMs and AAs. The recurrent AA and residual size of cAVMs were used to evaluate the outcomes of patients after treatment. At the same time, the ROC curve was measured to gauge the relationship between the residual size of cAVMs and recurrent AAs in eligible patients. Results Fifty (15.0%) patients with cAVMs and AA were confirmed; these patients had twice the hazard of hemorrhage as patients with only isolated cAVMs. An infratentorial location ( P P = 0.002) were independent predictors of the formation of AAs. After a mean 22.7 months follow-up, 2 patients developed recurrent AAs, and the annual recurrence rate for patients with responsible characteristics was 17.6%, but for all patients was 7.2%. The ROC curve showed that patients, specifically patients with responsible characteristics, the residual size of the cAVM was closely related to recurrent AA (area = 0.89, 95% confidence interval 0.81−0.97, P = 0.023, cut-off value = 82.5%). Conclusions Patients with cAVMs and AA who harbor a fistula or an infratentorial location tend to form AAs. To prevent recurrent AAs and decrease the subsequent risk of hemorrhage, complete obliteration of cAVMs or retrograding over 80% size of cAVMs is recommended.

The flux motion and its collective behaviour known as AC loss is the basic characteristic of high temperature superconducting (HTS) materials and controls the economic efficiency, stability and magnetic field uniformity of superconducting equipment. In so far, we have no method to calculate the AC loss of HTS devices in an efficient way. Normally, it will take days to simulate AC loss of HTS coils even with moderate number of turns. In this paper, we surprisingly found that an integral method is remarkably efficient in calculating AC loss of the coils in large scale. By comparing with the fastest method at present, the integral method is proved to be 4.4 times faster than the present one. We give the calculation details and discuss why this method has an advantage in calculating AC loss of the coil with a large number of turns.

Aneurysm recurrence is a principle limitation of endovascular coiling procedures, especially in posterior communicating artery aneurysms, with reported recurrence rates of >30%. The adjunctive use of self-expandable stents has revolutionised the treatment of intracranial aneurysms, especially for complex morphologies, wide necks, or unfavourable dome-to-neck ratios. However, there are limited data concerning a direct comparison between simple coiling and stent-assisted coiling in posterior communicating artery aneurysms. This study aimed to compare the durability and outcomes of coiling versus stent-assisted coiling procedures. Imaging data of patients with posterior communicating artery aneurysms treated with coiling or stent-assisted coiling between January 2008 and October 2012 were retrospectively analysed. The initial angiographic results, procedural complications, and clinical outcomes were assessed at discharge. Imaging follow-up was performed with cerebral angiography. Complete aneurysm occlusion was achieved on initial angiography in 23/56 (41.1%) stent and 83/235 (35.3%) non-stent patients. At the latest follow-up (mean follow-up 14.3 ± 10.4 months for stent and 13.2 ± 9.5 months for non-stent patients), aneurysms had recurred in 5/47 (10.6%) stent and 57/203 (28.1%) non-stent patients (p = 0.014). Procedural complications occurred in 6/56 (10.7%) stent and 27/235 (11.5%) non-stent aneurysms. No rebleeding occurred during clinical follow-up (mean duration, 46.7 months). Recurrence rates at the latest follow-up were significantly lower in patients undergoing stent-assisted coiling than those undergoing simple coiling. Thus, use of the stent-assisted neck remodelling technique in the treatment of wide-necked posterior communicating artery intracranial aneurysms appears to improve the long-term clinical outcome.

The purpose of this study was to characterize clinical features and evaluate the clinical outcome of endovascular embolization treatment intracranial arteriovenous malformations in pediatric patients. A cohort of children (age ≤ 18 years) with arteriovenous malformations (AVMs) from 2000 to 2012 was included. Predictors studied included patient gender, age, and angioarchitectural features, including AVM location, nidus morphology and size, venous drainage, and associated aneurysms. Treatment method, complications and outcomes were recorded. The features of AVMs were evaluated before the treatment. One hundred twenty-seven children (77 males, mean age 13.2 years) were included; 90/127 (70.9 %) children were presented with hemorrhage. AVM size and deep venous drainage were independently associated with hemorrhage; 66/127 patients (52 %) treated with endovascular embolization. Complete obliteration at the end of all endovascular procedures was achieved in 14/66 patients (21.2 %), with an average of 78 % (range, 20–100 %) volume reduction. A mean of 2.9 (range, 1–9) feeding pedicles was embolized per patient. Overall, nine complications occurred in a total of 123 procedures (7.3 %). There was no procedure-related death in this study population. There was no significant difference between patients with and without complications in terms of AVM grade, demographic characteristics, or embolization features. AVM size and deep venous drainage were independently associated with hemorrhage in pediatric patients. Endovascular procedure is feasible and safe for pediatric AVMs, and complete embolization can be achieved in small AVMs, while large AVMs can be adequately reduced in size for additional microsurgery or stereotactic radiosurgery.

To characterise the safety, efficacy and cost of direct carotid-cavernous fistula (CCF) treatment using polyvinyl alcohol copolymer or detachable balloons. We reviewed retrospectively patients with direct CCFs treated with either a detachable balloon or polyvinyl alcohol copolymer at our hospital from 2005 to 2015 and identified 94 patients with 105 CCFs. All patients had follow-up angiograms. The CCF occlusion rate, procedure complication rate, treatment expense and operation time were recorded. With a mean of 5.4 months of angiographic follow-up, the complete occlusion rate and recanalisation rate of the polyvinyl alcohol copolymer group was not significantly different from that of the detachable balloon group. The treatment expense was much higher and the operation time was much longer in the polyvinyl alcohol copolymer group than the detachable balloon group (P

Previous studies have demonstrated that baicalein has protective effects against several diseases, which including ischemic stroke. The effect of baicalein on the blood-brain barrier (BBB) in intracerebral hemorrhage (ICH) and its related mechanisms are not well understood. We aimed to investigate the mechanisms by which baicalein may influence the BBB in a rat model of ICH. The rat model of ICH was induced by intravenous injection of collagenase IV into the brain. Animals were randomly divided into three groups: sham operation, vehicle, and baicalein group. Each group was then divided into subgroups, in which the rats were sacrificed at 24 and 72 h after ICH. We assessed brain edema, behavioral changes, BBB leakage, apoptosis, inducible nitric oxide synthase (iNOS), zonula occludens (ZO)-1, Mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB). Treatment with baicalein reduced brain water content, BBB leakage, apoptosis, and neurologic deficits, compared with vehicle. Baicalein also decreased ICH-induced changes in the levels of iNOS but increased the levels of ZO-1. The protective effect of baicalein on the BBB in ICH rats was possibly invoked by attenuated p-38 MAPK and JNK phosphorylation, and decreased activation of the NF-κB signaling pathway, which may have suppressed gene transcription, including iNOS, and eventually decreased formation of peroxynitrite (ONOO-). Our results suggest that baicalein exerts a protective effect on BBB disruption in the rat model of ICH. The likely mechanism is via inhibition of MAPKs and NF-κB signaling pathways, leading to decreased formation of iNOS and ONOO-, thereby improving neurological function.

BACKGROUND AND PURPOSE: The incidence of unruptured intracranial aneurysms is increasing in the elderly population as life expectancy increases, and patients often present with headache. The goal of this study was to determine the effect of endovascular treatment on headache and identify factors associated with headache outcome in elderly patients with unruptured intracranial aneurysms. MATERIALS AND METHODS: A retrospective study was conducted for elderly patients (≥ 65 years old) being treated for unruptured intracranial aneurysms. Headache assessment was performed by a quantitative 11-point headache scale in all patients before and after endovascular treatment. Factors associated with headache outcome were investigated by univariate analyses. RESULTS: A total of 72 patients (mean age, 70.0 years; age range, 65–80 years; 41 women) fulfilled the inclusion criteria. There were 52 patients (72.2%) who presented with preoperative headache (headache score ≥ 1). Among them, 40 (76.9%) reported that headache score had an improvement according to their self-reported quantitative headache score after endovascular treatment. The average headache score was 5.63 preoperatively vs 2.50 postoperatively ( P = .000). Twenty patients (27.8%) had no headache before treatment (headache score = 0), of whom 2 (10.0%) reported new onset of headache postoperatively. Only a preoperative headache score was associated with treatment outcome of headache, and a higher headache score predicted a lack of headache relief after endovascular treatment ( P = .003). CONCLUSIONS: Endovascular coiling of unruptured intracranial aneurysms resulted in relief of headache in most of the elderly patients. Preoperative headache score was the only statistically significant predictor of headache outcome.

Two kinds of green mono-filament Bi-2223/Ag superconducting tapes (T-phase tape and O-phase tape) were investigated, the initial superconducting phase of which was tetragonal Bi-2212 phase and orthorhombic (Bi,Pb)-2212 phase, respectively. The resistance of these tapes was in situ measured during heating at various oxygen partial pressures. It was found that the resistance increased at a characteristic temperature at every oxygen partial pressure. This resistance behavior was related to the formation of the liquid phase. The formation temperature of the liquid phase increased with increasing oxygen partial pressure. And the formation temperature of the liquid phase of T-phase tape was about 6 °C higher than that of O-phase tape. The above results demonstrated that the in situ resistance measurement is a sensitive method for studying the formation of the liquid phase in superconducting materials.

Posterior fossa brain arteriovenous malformations (PFbAVM) are relatively rare brain disorders but have a high risk of hemorrhage. Endovascular embolization to reduce the lesion size before treatment may improve the outcome of PFbAVM. The purposes of this study were to identify risk factors associated with hemorrhage in PFbAVM and to assess clinical outcomes in patients receiving initial endovascular embolization. From 1999 to 2013 a total of 63 patients with PFbAVMs were treated (31 males and 32 females, 14.1 % of all AVM cases). A retrospective examination of patient demographics, clinical presentation, angiographic features, treatment modalities, complications and outcomes was carried out. The re-hemorrhage rate, obliteration rate and modified Rankin scale (MRS) were used as measures of outcome. Of the 63 PFbAVM patients 54 (85.7 %) exhibited hemorrhage and 15 had confirmed aneurysms. The cerebellar location (P = 0.007) and deep venous drainage (P = 0.012) were independent predictors of hemorrhage in multivariate analyses. The mean estimated devascularization was 46.9 % (range 10–100 %) in the 20 patients (31.7 %) treated by endovascular embolization. The 16 patients with residual niduses were further treated by radiosurgery, microsurgery or embolization. Complete obliteration was attained in 12 patients (67 %) while 2 (5.7 %) were left with persisting neurological deficits and 1 had a re-hemorrhage 3 years later (annual rate of 4.6 %). Favorable outcome (MRS ≤ 2) was obtained in the 20 patients receiving initial endovascular embolization (P = 0.039 versus preoperative MRS). Cerebellar location and deep venous drainage are predictors of hemorrhage in PFbAVM. Adjuvant endovascular embolization is useful and safe for PFbAVM prior to microsurgery or radiosurgery.

The purpose of this study was to determine the safety and effectiveness of cerebellar arteriovenous malformations (AVMs) embolization and find out the suitable methods to manage associated aneurysms. Medical records of all patients between 1997 and 2014 with a diagnosis of cerebellar AVMs were retrospectively reviewed. Univariable and multivariable logistic analysis were used to assess AVMs characteristics to calculate for the risk of hemorrhage. Endovascular treatment was the main treatment measure to manage the AVMs and associated aneurysms. Of 142 patients, 115 (81.0 %) presented with hemorrhage and 42 (29.6 %) with associated aneurysms. A significant association with cerebellar AVMs hemorrhage was found for small size, prenidal aneurysms, and deep venous drainage in the univariable and multivariable analysis. Associated aneurysms were treated firstly in 41 patients except for 1 patient with 2 prenidal and 2 intranidal aneurysms. The special case was dealt with AVMs and 2 intranidal aneurysms first and angiography showed that the 2 prenidal associated aneurysms disappeared with time. Hemorrhage appeared in 13/142 patients (9.2 %) during the follow-up period, none of which was with associated aneurysms. Endovascular treatment can be a feasible way for treating cerebellar AVMs. Intranidal associated aneurysms should be treated first. Prenidal associated aneurysms can be treated later depending on the angioarchitecture of AVMs.

Background Mesenchymal stem cells (MSCs) are well known having beneficial effects on intracerebral hemorrhage (ICH) in previous studies. The therapeutic mechanisms are mainly to investigate proliferation, differentiation, and immunomodulation. However, few studies have used MSCs to treat blood–brain barrier (BBB) leakage after ICH. The influence of MSCs on the BBB and its related mechanisms were investigated when MSCs were transplanted into rat ICH model in this study. Methods Adult male Sprague–Dawley (SD) rats were randomly divided into sham-operated group, PBS-treated (ICH + PBS) group, and MSC-treated (ICH + MSC) group. ICH was induced by injection of IV collagenase into the rats’ brains. MSCs were transplanted intravenously into the rats 2 h after ICH induction in MSC-treated group. The following factors were compared: inflammation, apoptosis, behavioral changes, inducible nitric oxide synthase (iNOS), matrix metalloproteinase 9 (MMP-9), peroxynitrite (ONOO−), endothelial integrity, brain edema content, BBB leakage, TNF-α stimulated gene/protein 6 (TSG-6), and nuclear factor-κB (NF-κB) signaling pathway. Results In the ICH + MSC group, MSCs decreased the levels of proinflammatory cytokines and apoptosis, downregulated the density of microglia/macrophages and neutrophil infiltration at the ICH site, reduced the levels of iNOS and MMP-9, attenuated ONOO− formation, and increased the levels of zonula occludens-1 (ZO-1) and claudin-5. MSCs also improved the degree of brain edema and BBB leakage. The protective effect of MSCs on the BBB in ICH rats was possibly invoked by increased expression of TSG-6, which may have suppressed activation of the NF-κB signaling pathway. The levels of iNOS and ONOO−, which played an important role in BBB disruption, decreased due to the inhibitory effects of TSG-6 on the NF-κB signaling pathway. Conclusions Our results demonstrated that intravenous transplantation of MSCs decreased the levels of ONOO− and degree of BBB leakage and improved neurological recovery in a rat ICH model. This strategy may provide a new insight for future therapies that aim to prevent breakdown of the BBB in patients with ICH and eventually offer therapeutic options for ICH.

Summary Purpose The recovery time of traumatic carotid-cavernous fistula-induced oculomotor nerve paresis (ONP) after endovascular embolization with detachable balloons has not yet been adequately evaluated. This study was performed to make a deep analysis of the factors, which affect the prognosis of ONP after endovascular treatment of traumatic carotid-cavernous fistula (TCCF). Materials and methods We retrospectively evaluated the clinical characteristics and the outcome of oculomotor nerve function in a series of 98 consecutive patients with ONP due to traumatic carotid-cavernous fistula which were endovascular treated with detachable balloons. Univariate analysis was applied to test the association between the time of ONP recovery and clinical variables. Results Ninety-eight consecutive patients (62 males, 36 females, mean age 34.2 ± 12.7 years) having presented with ONP underwent endovascular treatment with detachable balloons were enrolled in this study. ONP was complete in 22 (22.4%) patients and partial in 76 (77.6%) patients. Ninety (91.8%) patients were successfully occluded by single-session endovascular embolization. Retreatments by transarterial routes had to be performed in 8 (8.2%) patients because of recurrent fistula having occurred within 4 weeks after embolization. ONP was recovered completely in all the patients, among who 4 (4.1%) were treated with occlusion of internal carotid artery. Factors showing significant association with the recovery time of ONP were the location of the fistula (P = 0.007), the degree of preoperative ONP (P = 0.003), the number of detachable balloon used (P = 0.000) and the length of ONP before endovascular treatment (P = 0.000). Conclusion Endovascular treatment of traumatic carotid-cavernous fistula-induced ONP with detachable balloons is a safe and effective method. The length of ONP before endovascular treatment, the location of the fistula, the degree of preoperative ONP, the number of detachable balloons used were the statistically significant predictors of the length of ONP complete recovery.