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Purpose: The etiological features of stroke in young adults are different from those in older adults. We aimed to investigate the impact of high-resolution vessel wall imaging (HRVWI) on etiologic diagnosis in young adults with ischemic stroke or transient ischemic attack (TIA). Methods: A total of 253 young adults (aged 18–45 years) who consecutively underwent HRVWI for clarifying stroke etiology were retrospectively recruited. Two experienced neurologists classified stroke etiology for each patient using Trial of Org 10,172 in Acute Stroke Treatment categories with and without the inclusion of HRVWI diagnosis. Multivariate logistic regression was performed to determine which etiologic category would be significantly impacted after including HRVWI. Results: The etiologic classification was altered in 39.1% (99/253) of patients after including HRVWI in the conventional investigations. The proportion of patients classified as having stroke of undetermined etiology (SUE) and the proportion of patients classified as having small-artery occlusion (SAO) both significantly decreased (36.4 to 13.8% and 9.1 to 2.0%), whereas the proportion of patients classified as having large artery atherosclerosis (LAA) significantly increased (28.5 to 58.1%) (all P < 0.001). The inclusion of HRVWI had a significant diagnostic impact on young adults who were primarily classified as SAO (odds ratio [OR] 14.4, 95% confidence interval [CI] [2.9, 71.8], P < 0.001) or SUE (OR 8.3, 95% CI [2.2, 31.5], P < 0.01). Conclusions: HRVWI had a substantial impact on etiologic classification in young adults with ischemic stroke or TIA, particularly for those primarily classified as having SAO or SUE. This impact of HRVWI will be beneficial for therapeutic decision-making. [ABSTRACT FROM AUTHOR]

This article discusses the use of multiphase MR angiography collateral maps in the treatment of acute ischemic stroke (AIS) and large vessel occlusion. Collateral circulation, which varies among patients, plays a crucial role in determining the rate of ischemic penumbra recruitment and infarct growth. The article explores different imaging techniques for evaluating collateral flow, including digital subtraction angiography, single-phase computed tomography angiography (sCTA), and multiphase CTA (mCTA). It also introduces a novel collateral imaging method using time-resolved dynamic contrast-enhanced MR angiography. The study findings suggest that MR imaging-based collateral maps can accurately predict lesion growth and salvageable tissue, potentially improving the results of recanalization treatments. However, further studies are needed to confirm the reliability and generalizability of these findings. [Extracted from the article]

Objective: To investigate the value of automated Alberta Stroke Program Early CT Score (ASPECTS)-based net water uptake (NWU) to predict tissue-level reperfusion status and 90-day functional outcomes in acute ischemic stroke (AIS) patients after reperfusion therapy.Methods: One hundred and twelve patients with AIS who received reperfusion therapy were enrolled. ASPECTS-NWU was calculated from admission CT (NWUadmission) and follow-up CT (NWUFCT), and the difference (ΔNWU) was calculated. Tissue-level reperfusion status was evaluated via follow-up arterial spin labeling imaging. The relationship between ASPECTS-NWU and tissue-level reperfusion was evaluated. Predictors of 90-day unfavorable outcomes (modified Rankin Scale score > 2) were assessed by multivariate logistic regression analysis and receiver operating characteristic (ROC) curves.Results: Poor reperfusion was observed in 40 patients (35.7%) after therapy. Those patients had significantly elevated NWUFCT (median, 14.15% vs. 8.08%, p = 0.018) and higher ΔNWU (median, 4.12% vs. -2.03%, p < 0.001), compared to patients with good reperfusion. High ΔNWU was a significant marker of poor reperfusion despite successful recanalization. National Institutes of Health Stroke Scale score at admission (odds ratio [OR], 1.11; 95% confidence interval [CI] 1.03-1.20, p = 0.007) and ΔNWU (OR, 1.07; 95% CI 1.02-1.13, p = 0.008) were independently associated with unfavorable outcomes. An outcome prediction model including both parameters yields an area under the curve of 0.762 (sensitivity 70.3%, specificity, 84.2%).Conclusions: Elevated NWUFCT and higher ΔNWU were associated with poor tissue-level reperfusion after therapy. Higher ΔNWU was an independent predictor of poor reperfusion and unfavorable neurological outcomes despite successful recanalization.Key Points: • ASPECTS-NWU may provide pathophysiological information about tissue-level reperfusion status and offer prognostic benefits for patients with AIS after reperfusion therapy. • Elevated NWUFCT and higher ΔNWU were correlated with poor tissue-level reperfusion after therapy. • A higher ΔNWU is an independent predictor of poor reperfusion and 90-day unfavorable outcomes despite successful recanalization. [ABSTRACT FROM AUTHOR]

The recently reported two-dimensional lead halide perovskites have attracted much attention in high-energy radiation detector applications due to its high structural stability and low ion migration. However, the increased exciton binding energy and the charge transport barrier resulting from the A-site cation can easily limit the charge extraction and device performance. As an emerging material in high-energy detection field, guanidinium {GA+ = [C(NH2)3]+} is a relatively large organic cation composed of three amino groups, which can enhance the hydrogen bond formation and the van der Waals interactions with the metal halide framework. Meanwhile, the polymer symmetry of GA+ cation leads to almost zero dipole moments, excellent electronic properties, and high thermodynamic stability. However, there is a lack of report on the preparation, structure, and properties of GA-based 2D perovskite single crystals as well as their applications in x-ray detection. Herein, we have synthesized large-size two-dimensional GA2PbI4 single crystals with a bandgap of 2.28 eV by cooling crystallization and applied them to x-ray detectors. GA2PbI4 single crystals exhibit a high μτ product of 7.5 × 10−4 cm2 V−1 and a low trap density of 6.44 × 108 cm−3. An effective x-ray photoresponse was realized with a sensitivity as high as 392.4 μC Gyair−1 cm−2. The unique structure and excellent charge transport properties of GA+ organic cations exhibit promising prospects in high-performance x-ray detection. [ABSTRACT FROM AUTHOR]

Objectives: To compare collateral status on single-phase CT angiography (sCTA) and multiphase CT angiography (mCTA) and their ability to predict a target mismatch on CT perfusion (CTP) and clinical outcome in patients with acute ischemic stroke (AIS).Methods: Seventy-three AIS patients with stroke onset between 5 and 15 h or with unclear onset time and occlusions in the M1/M2 segment of the middle cerebral artery and/or intracranial internal carotid artery underwent head non-contrast CT and CTP. Simulated sCTA and mCTA were reconstructed from CTP data and were compared for collaterals assessment. The ability to predict target mismatch on CTP (an ischemic core < 70 ml, a mismatch ratio ≥ 1.8, and an absolute difference ≥ 15 ml) and 90-day modified Rankin Scale (mRS) score of 0-2 was compared between sCTA and mCTA by using receiver operating curve analysis.Results: sCTA underestimated the collateral status when compared with mCTA (p < 0.01). The ability of mCTA to predict target mismatch (AUC = 0.902, 95% confidence interval [CI] 0.809, 0.959) and clinical outcome (AUC = 0.771; 95% CI, 0.655, 0.864) was better than that of sCTA (p < 0.05 overall). A mCTA collateral score of > 3 best identified the target mismatch (sensitivity, 78.4%; specificity, 90.9%) and predicted 90-day mRS score of 0-2 (sensitivity, 84.8%; specificity, 69.4%).Conclusions: The collaterals were better estimated by mCTA compared with sCTA. A mCTA collateral score of > 3 optimized the prediction of a target mismatch on CTP and a good clinical outcome in patients with AIS.Key Points: • Collateral circulation is a key determinant of ischemic core and penumbra. Better collaterals are associated with smaller ischemic core volumes and larger mismatch ratios on CT perfusion. • The collaterals can be better estimated by multiphase CTA compared with single-phase CTA. • A collateral score of > 3 on multiphase CTA best identifies patients with target mismatch on CT perfusion and predicts 90-day mRS score of 0-2. [ABSTRACT FROM AUTHOR]

• A new kind of hybrid perovskite DMAPbI 3 perovskite single crystal with centimeter-sized and suitable bandgap was grown. • Cu ion implantation can effectively eliminate the metallic lead defects. • Ultra-high X-ray sensitivity and enhanced irradiation stability of Cu ion implanted DMAPbI 3 X-ray detectors were achieved. • The Cu ion implanted detectors were demonstrated to have good environmental stability and radiation resistance. Lead halide perovskite single crystals are one of the most promising materials for radiation detection due to their unique advantages of excellent attenuation efficiency, large carrier mobility, long carrier diffusion length, and low defect density. However, the relatively low irradiation stability and severe ion migration in perovskites deteriorate the X-ray detection performance under longtime and high-field operating conditions. Herein, we synthesize a centimeter-sized organometal halide perovskite of DMAPbI 3 single crystals. The effective modification strategy of Cu ion implantation is employed to suppress the ion migration and significantly improve the irradiation stability and the performance of DMAPbI 3 in X-ray detection. The modification effect is evidenced by the effectively eliminated metallic lead (Pb0) defects, extends the carrier decay lifetime, increases the photoluminescence (PL) intensity and improves μτ product. As a result, the coplanar X-ray detectors with Cu ion treatment exhibits a shorten transient response time of 522 μs, an excellent sensitivity up to 11,066 μC Gy air −1 cm−2 under 50 V as well as a low detection limit of 0.16 μGy air s−1. Moreover, the combination of high stability and excellent X-ray response enables superior X-ray imaging. Finally, the DFT calculation is employed to unravel the mechanisms of implanted Cu ions induced reduction of non-radiative charge recombination and improvement of the interface charge carrier extraction efficiency. This work provides effective interface passivation strategy and insights for improving the performance of perovskite X-ray detectors. [ABSTRACT FROM AUTHOR]

Developing effective and robust electrocatalysts that are applicable for different pH conditions is promising for variable industrial hydrogen evolution reaction (HER), whereas it remains challenging for designing proper materials and protocols. Herein, we have developed a two-step electrodeposition-hydrothermal strategy to construct heterostructured binary Ni-W sulfides nanosheets based on carbon fiber (NiWS/CF). The electrodeposited nickel oxides film on CF in the first step is sulfurized and concurrently incorporated with tungsten disulfide in the following hydrothermal process. Benefiting from synergistic advantages of bimetallic sulfides as well as interwoven nanosheets for efficient mass/charge transport, the NiWS/CF electrode shows excellent HER performances over a broad pH range from acidic (pH = 0), neutral (pH = 7) to alkaline (pH = 14) media. The NiWS/CF electrode also presents stability in long-term electrolysis in wide PH range for at least 12 h, and its interlaced nanosheets structure are well maintained. Our work may provide general and promising strategies to obtain inexpensive and efficient electrocatalysts for pH-universal hydrogen production. [ABSTRACT FROM AUTHOR]

Background The association between the extended tau haplotype (H1) and susceptibility to Parkinson’s disease (PD) was controversial in previous studies. Therefore, we performed this meta-analysis to determine whether the additional polymorphisms in MAPT_238bp and STH Q7R which both included in H1 are associated with PD. Methods 19 studies were identified by a search of PubMed, PDGENE, Elsevier, Springer Link, CBM (Chinese Biomedical Database), CNKI (Chinese National Knowledge Infrastructure), VIP (Chinese), and Wanfang (Chinese) databases, up to May 2014. Additionally, manual retrieval of the references of identified articles was performed. Odds ratios (ORs) with 95% confidence interval (CI) were calculated using random effects model or fixed effects model based on the between-study heterogeneity. The subgroup analyses were performed by the ethnicity. All the statistical tests were conducted using Stata 9.0. Results Both of MAPT_238bp/STH Q7R polymorphisms had a significant association with PD risk in all genetic models. Subgroup analyses by ethnicity showed that the association between MAPT_238bp polymorphism and PD existed in Caucasian populations. Conclusions The results of this meta-analysis suggested that MAPT_238bp/STH Q7R polymorphisms might modulate the risk of PD susceptibility. Certainly, additional well-designed studies are required to confirm these findings. [ABSTRACT FROM AUTHOR]

Objectives: To assess the predictors of ghost infarct core (GIC) in stroke patients achieving successful recanalization after mechanical thrombectomy (MT), based on final infarct volume (FIV) calculated from follow-up diffusion-weighted imaging (DWI). Methods: A total of 115 consecutive stroke patients who had undergone baseline computed tomography perfusion (CTP) scan, achieved successful recanalization after MT, and finished follow-up DWI evaluation were retrospectively enrolled. Ischemic core volume was automatically generated from baseline CTP, and FIV was determined manually based on follow-up DWI. Stroke-related risk factors and demographic, clinical, imaging, and procedural data were collected and assessed. Univariate and multivariate analyses were applied to identify the predictors of GIC. Results: Of the 115 included patients (31 women and 84 men; median age, 66 years), 18 patients (15.7%) showed a GIC. The GIC group showed significantly shorter time interval from stroke onset to CTP scan and that from stroke onset to recanalization (both p < 0.001), but higher ischemic core volume (p < 0.001), hypoperfused area volume (p < 0.001), mismatch area volume (p = 0.006), and hypoperfusion ratio (p = 0.001) than the no-GIC group. In multivariate analysis, time interval from stroke onset to CTP scan (odds ratio [OR], 0.983; p = 0.005) and ischemic core volume (OR, 1.073; p < 0.001) were independently associated with the occurrence of GIC. Conclusions: In stroke patients achieving successful recanalization after MT, time interval from stroke onset to CTP and ischemic core volume are associated with the occurrence of GIC. Patients cannot be excluded from MT solely based on baseline CTP-derived ischemic core volume, especially for patients with a shorter onset time. Key Points: • Ghost infarct core (GIC) was found in 15.7% of patients with acute ischemic stroke (AIS) in our study cohort. • GIC was associated with stroke onset time, volumetric parameters derived from CTP, and collateral status indicated by HIR. • Time interval from stroke onset to CTP scan and ischemic core volume were independent predictors of GIC. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the feasibility of intraarterial (IA) delivery and in vivo MR imaging of superparamagnetic iron oxide (SPIO)-labeled mesenchymal stem cells (MSCs) in a canine stroke model. Methodology: MSCs harvested from beagles’ bone marrow were labeled with home-synthesized SPIO. Adult beagle dogs (n = 12) were subjected to left proximal middle cerebral artery (MCA) occlusion by autologous thrombus, followed by two-hour left internal carotid artery (ICA) occlusion with 5 French vertebral catheter. One week later, dogs were classified as three groups before transplantation: group A: complete MCA recanalization, group B: incomplete MCA recanalization, group C: no MCA recanalization. 3×106 labeled-MSCs were delivered through left ICA. Series in vivo MRI images were obtained before cell grafting, one and 24 hours after transplantation and weekly thereafter until four weeks. MRI findings were compared with histological studies at the time point of 24 hours and four weeks. Principal Findings: Home-synthesized SPIO was useful to label MSCs without cell viability compromise. MSCs scattered widely in the left cerebral hemisphere in group A, while fewer grafted cells were observed in group B and no cell was detected in group C at one hour after transplantation. A larger infarction on the day of cell transplantation was associated with more grafted cells in the brain. Grafted MSCs could be tracked effectively by MRI within four weeks and were found in peri-infarction area by Prussian blue staining. Conclusion: It is feasible of IA MSCs transplantation in a canine stroke model. Both the ipsilateral MCA condition and infarction volume before transplantation may affect the amount of grafted cells in target brain. In vivo MR imaging is useful for tracking IA delivered MSCs after SPIO labeling. [ABSTRACT FROM AUTHOR]

Abstract: Background: Accumulating evidence suggests that the occurrence of oxidative stress leads to melanocyte degeneration in vitiligo. Elevated level of dopamine (DA), an initiator of oxidative stress, reportedly is found in patients with vitiligo and induces melanocyte death in vitro. DA-treated melanocytes have been used as a model to search for antioxidants for treating vitiligo. Objective: We investigated the protective effects of apigenin against DA-induced apoptosis in melanocytes and the molecular mechanism underlying those effects. Methods: Melanocytes with or without pretreatment with apigenin were exposed to DA. Then cell viabilities were measured by MTT assay. Cellular reactive oxygen species (ROS) levels and the percentage of apoptotic cells were detected by flow cytometry analysis. Activation of caspase 3, poly(ADP-ribose) polymerase (PARP) and oxidative stress-related signaling, including p38, c-Jun NH2-terminal kinase (JNK) and Akt, were assessed by Western blotting. Results: Apigenin attenuated DA-induced apoptotic cell death, relieved ROS accumulation and activated caspase 3 and PARP, suggesting the protective effects of apigenin against DA-induced oxidative stress and apoptosis in melanocytes. Moreover, DA induced phosphorylation of p38, JNK and Akt, while inhibitors of p38, JNK and Akt significantly decreased DA-induced apoptosis. However, pretreatment with apigenin significantly inhibited DA-triggered activation of p38, JNK and Akt, suggesting the involvement of p38, JNK and Akt in the protective effects of apigenin against DA-induced cytotoxicity. Conclusion: These results suggest that apigenin attenuates dopamine-induced apoptosis in melanocytes via oxidative stress-related p38, JNK and Akt signaling and therefore could be a potential agent in treating vitiligo. [Copyright &y& Elsevier]

This paper develops a successive approximation approach (SAA) of optimal sliding mode control (SMC) for linear time-delay systems with sinusoidal disturbances. A sequence of two-point boundary value (TPBV) problems with both time-delay and time-advance terms is derived from the optimal sliding mode design. According to the SAA, the original TPBV problems are transformed into a sequence of linear TPBV problems without delay and advance terms. The obtained SMC ensures that the state trajectories reach the sliding surface in finite time and remain on it thereafter. The stability of the sliding mode is proved. A numerical simulation is employed to verify the effectiveness of the proposed approach. [Copyright &y& Elsevier]

Two-dimensional (2D) perovskites have been demonstrated great promise in x-ray detection application because of their stability, tunability, and the unique electronic properties. The centimeter-sized 2D perovskite (PMA)2PbI4 single crystal and the corresponding x-ray detector were fabricated. The Cu ion implanted device exhibits an excellent sensitivity of 283 μC Gyair−1 cm−2, the significantly enhanced mobility-lifetime (μτ) product of 8.05 × 10−3 cm2 V−1, and the lowest detectable dose rate of 2.13 μGyair s−1. Experimental observation combined with the DFT calculations shows that the improvement in Cu ion implanted x-ray detection is ascribed to the enhanced photoinduced charge carrier density and μτ product, and the increased carrier dissociation capability associated deeply with the decreased binding energy of exciton in the inorganic layer quasi-quantum well. The incorporation of the Cu interstitials by high-energy Cu ion implantation is able to introduce the donor and acceptor states with additional charge transfer channeling, resulting in the decreased exciton binding energy and fast dissociation of the exciton and the quick carrier extraction. Cu ion implantation regulating the dissociation of charge carriers in low-dimensional perovskites will motivate the application for 2D perovskite in high-performance x-ray detectors. [ABSTRACT FROM AUTHOR]

Background: Elevated plasma homocysteine (Hcy) is an independent risk factor for ischemic stroke. This study aimed to evaluate the association between Hcy levels and intracranial plaque characteristics and to investigate their clinical relevance in ischemic stroke.Methods: Ninety-four patients with intracranial atherosclerosis (ICAS) were enrolled. Plasma Hcy levels were measured. Intracranial plaque characteristics including plaque enhancement, stenosis ratio, T2 and T1 hyperintense components were assessed on high-resolution magnetic resonance imaging. Logistic regression model was constructed to analyze the association between high Hcy levels and plaque characteristics, and their synergistic effects to predict the likelihood for ischemic stroke, while adjusting for demographics and traditional atherosclerotic risk factors.Results: Elevated Hcy level was associated with strong plaque enhancement independently of age, sex, serum creatinine levels and other atherosclerotic risk factors ((P < 0.001, OR 6.00, 95% confidence interval [CI] 2.28-15.74). Both strong plaque enhancement (P = 0.026, OR 5.63, 95% CI 1.23-25.81) and high Hcy level (P = 0.018, OR 6.20, 95% CI 1.36-28.26) were correlated with acute ischemic stroke. The combination of them strengthened the ability to stratify the likelihood for ischemic stroke, with an improved area under the receiver operating characteristic curve (AUC) of 0.871, significantly higher than that of strong plaque enhancement (0.755) and high Hcy level (0.715) alone (P < 0.05 for both).Conclusions: High Hcy level appears to have association with intracranial strong plaque enhancement. The combined assessment of plasma Hcy levels and plaque enhancement may improve ischemic stroke risk stratification. [ABSTRACT FROM AUTHOR]

Objective: To compare the prognostic value of net water uptake (NWU) and target mismatch (TM) on CT perfusion (CTP) in acute ischemic stroke (AIS) patients with late time window. Methods: One hundred and nine consecutive AIS patients with anterior-circulation large vessel occlusion presenting within 6–24 h from onset/last seen well were enrolled. Automated Alberta Stroke Program Early CT Score–based NWU (ASPECTS-NWU) was calculated from admission CT. The correlation between ASPECTS-NWU and CTP parameters was assessed. Predictors for favorable outcome (modified Rankin Scale score ≤ 2) at 90 days were assessed using logistic regression analysis. The ability of outcome prediction between ASPECTS-NWU and TM (an ischemic core < 70 mL, a mismatch ratio ≥ 1.8, and an absolute difference ≥ 15 mL) was compared using receiver operating characteristic (ROC) curve. Results: A higher level of ASPECTS-NWU was associated with a larger ischemic core (r = 0.66, p < 0.001) and a larger hypoperfusion volume (r = 0.38, p < 0.001). ASPECTS-NWU performed better than TM for outcome stratification (area under the curve [AUC], 0.738 vs 0.583, p = 0.004) and was the only independent neuroimaging marker associated with favorable outcomes compared with CTP parameters (odds ratio, 0.73; 95% confidence interval [CI] 0.62–0.87, p < 0.001). An outcome prediction model including ASPECTS-NWU and clinical variables (National Institutes of Health Stroke Scale scores and age) yielded an AUC of 0.828 (95% CI 0.744–0.893; sensitivity 65.4%; specificity 87.7%). Conclusion: ASPECTS-NWU performed better than TM for outcome prediction in AIS patients with late time window and might be an alternative imaging biomarker to CTP for patient selection. Clinical relevance statement: Automated Alberta Stroke Program Early CT Score–based net water uptake outperforms target mismatch on CT perfusion for the outcome prediction in patients with acute ischemic stroke and can be an alternative imaging biomarker for patient selection in late therapeutic window. Key Points: • A higher ASPECTS-based net water uptake was associated with larger ischemic cores and hypoperfusion volumes on CT perfusion. • ASPECTS-based net water uptake outperformed target mismatch for outcome prediction in acute ischemic stroke with extended therapeutic window. • ASPECTS-based net water uptake can be an alternative biomarker to target mismatch for selecting acute ischemic stroke patients with late therapeutic window. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the ability of diffusion–relaxation correlation spectrum imaging (DR-CSI) to predict the consistency and extent of resection (EOR) of pituitary adenomas (PAs). Methods: Forty-four patients with PAs were prospectively enrolled. Tumor consistency was evaluated at surgery as either soft or hard, followed by histological assessment. In vivo DR-CSI was performed and spectra were segmented following to a peak-based strategy into four compartments, designated A (low ADC), B (mediate ADC, short T2), C (mediate ADC, long T2), and D (high ADC). The corresponding volume fractions ( f A , f B , f C , f D ) along with the ADC and T2 values were calculated and assessed using univariable analysis for discrimination between hard and soft PAs. Predictors of EOR > 95% were analyzed using logistic regression model and receiver-operating-characteristic analysis. Results: Tumor consistency was classified as soft (n = 28) or hard (n = 16). Hard PAs presented higher f B (p = 0.001) and lower f C (p = 0.013) than soft PAs, while no significant difference was found in other parameters. f B significantly correlated with the level of collagen content (r = 0.448, p = 0.002). Knosp grade (odds ratio [OR], 0.299; 95% confidence interval [CI], 0.124–0.716; p = 0.007) and f B (OR, 0.834, per 1% increase; 95% CI, 0.731–0.951; p = 0.007) were independently associated with EOR > 95%. A prediction model based on these variables yielded an AUC of 0.934 (sensitivity, 90.9%; specificity, 90.9%), outperforming the Knosp grade alone (AUC, 0.785; p < 0.05). Conclusion: DR-CSI may serve as a promising tool to predict the consistency and EOR of PAs. Clinical relevance statement: DR-CSI provides an imaging dimension for characterizing tissue microstructure of PAs and may serve as a promising tool to predict the tumor consistency and extent of resection in patients with PAs. Key Points: • DR-CSI provides an imaging dimension for characterizing tissue microstructure of PAs by visualizing the volume fraction and corresponding spatial distribution of four compartments ( f A , f B , f C , f D ). • f B correlated with the level of collagen content and may be the best DR-CSI parameter for discrimination between hard and soft PAs. • The combination of Knosp grade and f B achieved an AUC of 0.934 for predicting the total or near-total resection, outperforming the Knosp grade alone (AUC, 0.785). [ABSTRACT FROM AUTHOR]

Background: Non-invasive detection of isocitrate dehydrogenase (IDH) mutational status in gliomas is clinically meaningful for molecular stratification of glioma; however, it remains challenging. Purpose: To investigate the usefulness of texture analysis (TA) of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and histogram analysis of diffusion kurtosis imaging (DKI) maps for evaluating IDH mutational status in gliomas. Material and Methods: This retrospective study enrolled 84 patients with histologically confirmed gliomas, comprising IDH-mutant (n = 34) and IDH-wildtype (n = 50). TA was performed for the quantitative parameters derived by DCE-MRI. Histogram analysis was performed for the quantitative parameters derived by DKI. Unpaired Student's t -test was used to identify IDH-mutant and IDH-wildtype gliomas. Logistic regression and receiver operating characteristic (ROC) curve analyses were used to compare the diagnostic performance of each parameter and their combination for predicting the IDH mutational status in gliomas. Results: Significant statistical differences in the TA of DCE-MRI and histogram analysis of DKI were observed between IDH-mutant and IDH-wildtype gliomas (all P < 0.05). Using multivariable logistic regression, the entropy of Ktrans, skewness of Ve, and Kapp−90th had higher prediction potential for IDH mutations with areas under the ROC curve (AUC) of 0.915, 0.735, and 0.830, respectively. A combination of these analyses for the identification of IDH mutation improved the AUC to 0.978, with a sensitivity and specificity of 94.1% and 96.0%, respectively, which was higher than the single analysis (P < 0.05). Conclusion: Integrating the TA of DCE-MRI and histogram analysis of DKI may help to predict the IDH mutational status. [ABSTRACT FROM AUTHOR]

Designing mixed transition metal oxides with advantageous nanostructure is efficient access to highly-efficient electrocatalysts for hydrogen evolution reaction (HER) in water electrolysis due to more exposed active sites and synergistic effects in mixed metals. A hierarchically three-level nanostructure combining two types of mixed transition metal oxides on nickel foam (Ni 3 (VO 4 ) 2 @NiCo 2 O 4 /NF) has been synthesized through a two-step hydrothermal process. The hierarchically three level nanostructure comprises porous nickel foam as robust and conductive substrate in the bottom, vertical and uniform NiCo 2 O 4 nanowires arrays in the intermediate, and top-coated Ni 3 (VO 4 ) 2 nanoparticles in 10 nm. The triple hierarchical nanostructure of Ni 3 (VO 4 ) 2 @NiCo 2 O 4 /NF is favorable for enlarging surface areas, exposing more active sites, promoting mass and charge transfer and accelerating HER process. Ni 3 (VO 4 ) 2 @NiCo 2 O 4 /NF electrode can afford a current density of 10 mA cm −2 at a moderate overpotential of 113 mV with robust stability for at least 12 h. It may provide a new strategy to design triple hierarchical nanostructures based on earth-abundant transition metals to achieve large-scale production of hydrogen through water electrolysis in alkaline. [ABSTRACT FROM AUTHOR]

Highly efficient and metal-free electrocatalysts hold promising in industrial water electrolysis with low cost, environmental friendliness and structural stability in wide pH electrolyte. Herein, N and O dual-doped carbon fiber (CF-O-N) has been hydrothermally synthesized as a three-dimensional (3D) electrocatalyst for oxygen evolution reaction (OER). The co-doping of N and O atoms acts as dual-active-site to improve OER properties, while the rough surface and large pores in CF-O-N electrode may expose abundant active sites and sufficient contacting in catalyst/electrolyte interfaces. CF-O-N electrode behaves excellently for OER with only 130 and 590 mV to generate 10 mA cm −2 and 100 mA cm −2 , respectively. The superior OER property of CF-O-N electrode than single N- or O-doped CF implies the synergistic effect between N and O dopants that may further enhance OER activities. More importantly, dual-doped CF-O-N electrode displays roust stability in 10,000 cycles of cyclic voltammogram (CV) and 12 h chronoamperometry test with unchangeable structures proved by post physical characterizations. It may provide a facile and rational design of self-supported and metal-free materials with excellent activities for water oxidation and holds promising for further industrialization. [ABSTRACT FROM AUTHOR]

Mo 2 C@NC@MoS x porous nanospheres with sandwich shell have been synthesized for efficient hydrogen evolution in both acidic and alkaline media. Firstly, porous MoO 2 -Mo 2 C@NC nanospheres have been obtained with ultrafine Mo 2 C nanocrystallines as core and ultrathin N-doped carbon (NC) as shell through the carbonization of MoO 4 2- -/aniline-pyrrole (MoO 4 2- -Polymer) as precursor. Secondly, Mo 2 C@NC@MoS x porous nanospheres with sandwich shell have been synthesized by hydrothermal sulfurization, which can be confirmed by XPS and HRTEM. The sandwich shell is composed of ultrathin MoS x , NC layer and Mo 2 C nanocrystallines, which may reduce the strong Mo H bonding energy of pure Mo 2 C and lead to the suitable ΔG H* for HER. In addition, the ultrathin NC can prevent the aggregation of active sites and improve charge transfer rate due to rich N-doping. Mo 2 C@NC@MoS x exhibits enhanced performance and long-time durability in both acidic and alkaline solution. It requires a low onsetpotential of 119 mV, Tafel slope of 56 mV dec −1 in acidic solution and onsetpotential of 86 mV, Tafel slope of 90 mV dec −1 in alkaline solution. Therefore, designing sandwich nanostructure with better conductivity and optimized Mo H bonding energy may be a promising strategy for excellent Mo-based HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Developing cost-effective electrocatalysts with both high activity and stability remains challenging for oxygen evolution reaction (OER) in water electrolysis. Herein, based on V-doped nickel sulfide nanowire on nickel foam (NiVS/NF), we further conduct controllable electrodeposition of Fe hydroxides film on NiVS/NF (eFe/NiVS/NF) to further improve OER performance and stability. For comparison, ultrafast chemical deposition of Fe hydroxides on NiVS/NF (uFe/NiVS/NF) is also utilized. V-doping of NiVS/NF may introduce more active sites for OER, and nanowire structure can expose abundant active sites and facilitate mass transport. Both of the two depositions generate amorphous Fe hydroxides film covering on the surface of nanowires and lead to enhanced OER activities. Furthermore, electrodeposition strategy realizes uniform Fe hydroxides film on eFe/NiVS/NF confirmed by superior OER activity of eFe/NiVS/NF than uFe/NiVS/NF with relatively enhanced stability. The OER activity of eFe/NiVS/NF depends on various electrodepositon time, and the optimal time (15 s) is obtained with maximum OER activity. Therefore, the controllable electrodeposition of Fe may provide an efficient and simple strategy to enhance the OER properties of electrocatalysts. [ABSTRACT FROM AUTHOR]

A facile sulfurization process has been utilized to synthesize WS 2 /WO 3 heterostructure using WO 3 square nanosheets as support. The thin WO 3 nanosheets synthesized by hydrothermal method may provide large surface area with homogeneous dispersion, which is favorable for exposing active sites and fast charge transfer for hydrogen evolution reaction (HER). SEM and TEM images show that the thin square nanosheets of as-prepared WS 2 /WO 3 heterostructure are well kept after sulfurization process. The formation of WS 2 on the surface of heterostructured nanosheets may greatly enhance the intrinsic HER activity and conductivity. The electrochemical measurements demonstrate the obviously enhanced HER activity of WS 2 /WO 3 heterostructured nanosheets compared with pure WO 3 or bulk WS 2 , illustrating that the synergistic effect derived from heterostructured WS 2 /WO 3 may be a key to enhance HER performances of WO 3 . Therefore, designing heterostructure of transition metal sulfides/oxides may be a promising strategy to prepare efficient electrocatalysts for HER. [ABSTRACT FROM AUTHOR]

Background: Volumetric accuracy of using computed tomography perfusion (CTP) to estimate the post-treatment infarct in stroke patients with successful recanalization after mechanical thrombectomy (MT) has been studied a lot, however the spatial accuracy and its influence factors has not been fully investigated. Methods: This retrospective study reviewed the data from consecutive anterior large vessel occlusion (LVO) patients who had baseline CTP, successful recanalization after MT, and post-treatment diffusion-weighed imaging (DWI). Ischemic core on baseline CTP was estimated using relative cerebral blood flood (CBF) of < 30%. The infarct area was outlined manually on post-treatment DWI, and registered to CTP. Spatial agreement was assessed using the Dice similarity coefficient (DSC) and average Hausdorff distance. According to the median DSC, the study population was dichotomized into high and low Dice groups. Univariable and multivariable regression analyses were used to determine the factors independently associated with the spatial agreement. Results: In 72 included patients, the median DSC was 0.26, and the median average Hausdorff distance was 1.77 mm. High Dice group showed significantly higher median ischemic core volume on baseline CTP (33.90 mL vs 3.40 mL, P < 0.001), lower proportion of moderate or severe leukoaraiosis [27.78% vs 52.78%, P = 0.031], and higher median infarct volume on follow-up DWI (51.17 mL vs 9.42 mL, P < 0.001) than low Dice group. Ischemic core volume on baseline CTP was found to be independently associated with the spatial agreement (OR, 1.092; P < 0.001). Conclusions: CTP could help to spatially locate the post-treatment infarct in anterior LVO patients who achieving successful recanalization after MT. Ischemic core volume on baseline CTP was independently associated with the spatial agreement. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the feasibility of using CT perfusion (CTP) with increased temporal sampling interval to predict the target mismatch status in acute ischemic stroke (AIS) patients with anterior circular large-vessel occlusion (LVO). Methods: CTP with a sampling interval of 1.7 s (CTP1.7 s) was scanned in 77 AIS patients for pre-treatment evaluation. Simulated CTP data with sampling interval of 3.4 s (CTP3.4 s) or 5.1 s (CTP5.1 s) were reconstructed, respectively. Target mismatch was defined according to the EXTEND-IA (Extending the Time for Thrombolysis in Emergency Neurological Deficits—Intra-Arterial) and DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke) trial criteria, respectively. Pearson correlation analysis, Mann–Whitney U test, Bland–Altman analysis, and chi-square test were used for statistical analysis as appropriate. Results: Significant correlations were found on the volume of ischemic core, hypo-perfused area, mismatch area, and ratio between CTP1.7 s and CTP3.4 s or CTP5.1 s (all p < 0.001). There was no significant difference on the volume of ischemic core, hypo-perfused area, mismatch area, and mismatch ratio between CTP1.7 s and CTP3.4 s or CTP5.1 s (all p > 0.05). Compared with CTP1.7 s, CTP3.4 s or CTP5.1 s showed comparable performance in predicting the target mismatch status in the AIS patients with LVO (both p > 0.05). Conclusions: CTPs with increased temporal sampling intervals that lead to reduced radiation doses are feasible and may provide comparable performance in predicting target mismatch status in AIS patients with LVO. [ABSTRACT FROM AUTHOR]

Background: Target mismatch (ischemic core, mismatch volume and mismatch ratio) in patients with acute ischemic stroke (AIS) highly relies on the automated perfusion analysis software. Purpose: To evaluate the feasibility and accuracy of using the ABC/2 method to rapidly estimate the target mismatch on computed tomography perfusion (CTP) imaging in patients with AIS, using RAPID results as a reference. Material and Methods: In total, 243 patients with anterior circulation AIS who underwent CTP imaging were retrospectively reviewed. Target mismatch associated perfusion parameters were derived from RAPID results and calculated using the ABC/2 method. Paired t -test was used to assess the difference of volumetric parameters between the two methods. The ability of using the ABC/2 method to predict the important cutoff volumetric metrics was also evaluated. Result: There was no significant difference in the volumes of ischemic core (P = 0.068), ischemic area (P = 0.209), and mismatch volume (P = 0.518) between ABC/2 and RAPID. Using RAPID results as reference, the ABC/2 method showed high accuracy for predicting perfusion parameters (70 mL and 90 mL: sensitivity=98.5% and 98.5%, specificity=100% and 100%, positive predictive value [PPV]=100% and 100%, negative predictive value [NPV]=93.8% and 92.9%; 10 mL and 15mL: sensitivity=99.6% and 99.5%, specificity=55.6% and 50.0%, PPV=96.6% and 94.8%, NPV=90.9% and 92.3%; 1.2 and 1.8: sensitivity=99.6% and 94.8%, specificity=75.0% and 96.9%, PPV=98.7% and 99.5%, NPV=90.0% and 73.8%). Conclusion: The ABC/2 method may be a feasible alternative to RAPID for estimation of target mismatch parameters on CTP in patients with AIS. [ABSTRACT FROM AUTHOR]

Objectives: To explore the value of post-treatment fluid-attenuated inversion recovery vascular hyperintensity (FVH) in predicting clinical outcome in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). Methods: This retrospective study reviewed data from consecutive patients with large vessel occlusion of anterior circulation between July 2017 and February 2021. Together with other variables, status of post-treatment FVH was assessed for each patient. Good outcome was defined as a 3-month modified Rankin Scale score of 0–2. Chi-square test, Fisher's exact test, independent-samples t test, multivariate logistic regression analysis, and receiver operating characteristic analysis were used as appropriate. Results: Among 84 included patients, 48 (57.1%) patients showed post-treatment FVH. Post-treatment FVH significantly correlated with incomplete recanalization (p < 0.05) and low Alberta Stroke Project Early CT Changes Score on post-treatment diffusion-weighted imaging (p < 0.05). Higher incidence of hemorrhage transformation was observed in patients with post-treatment FVH than those without (27.1% vs. 16.7%); however, the difference did not reach significance (p = 0.259). Successful recanalization (odds ratio [OR], 0.024; 95% confidence interval [CI] 0.003–0.194; p < 0.05), lower National Institutes of Health Stroke Scale scores at admission (NIHSSpre) (OR, 1.196; 95% CI, 1.017–1.406; p < 0.05), and no post-treatment FVH (OR, 74.690; 95% CI, 4.624–1206.421; p < 0.05) were found to be independent predictors of good outcomes. Combined models integrating all three independent predictors (recanalization+NIHSSpre+post-treatment FVH) significantly outperformed the combined model without post-treatment FVH (recanalization+NIHSSpre) in predicting clinical outcome (p = 0.004). Conclusions: Post-treatment FVH may be an effective prognostic marker associated with clinical outcome in patients with AIS after EVT. Key Points: • Post-treatment FVH correlates with incomplete recanalization and higher infarct volume. • Post-treatment FVH is independently associated with an unfavorable outcome. • Post-treatment FVH may provide prognostic information in patients with AIS after EVT. [ABSTRACT FROM AUTHOR]

Objectives: To assess the prognostic value of Alberta Stroke Program Early Computed Tomography Score (ASPECTS) on post-treatment diffusion-weighted imaging (DWI) for acute ischemic stroke (AIS) patients after endovascular thrombectomy (EVT) and compare it with that of infarction volume. Methods: Ninety-eight consecutive AIS patients who underwent EVT and post-treatment DWI were retrospectively enrolled. ASPECTS and infarction volume were evaluated based on post-treatment DWI, respectively. Good clinical outcome was defined as modified Rankin Scale score of 0–2 at 90 days. Predictors of good clinical outcome were evaluated using univariate and multivariate logistic regression analysis. Prognostic value of post-treatment DWI ASPECTS and infarction volume were assessed and compared using receiver-operating-characteristic curves and the DeLong method. Results: Favorable outcome was achieved in 62 (63.3%) patients. A strong correlation was found between post-treatment DWI ASPECTS and infarction volume (ρ = −0.847). Due to strong correlation and potential collinearity, two multivariate logistic regression models were respectively developed which included post-treatment DWI ASPECTS or infarction volume. As a result, post-treatment DWI ASPECTS (OR, 2.401; 95%CI, 1.567–3.678; p < 0.001) and infarction volume (OR, 0.982; 95%CI, 0.846–0.998; p = 0.002) were both independent predictors of good clinical outcome. Setting post-treatment DWI ASPECTS ≥ 6 as a cut-off value, optimal performance (AUC = 0.836; sensitivity, 87.1%; specificity, 66.7%) could be obtained in predicting good clinical outcome, which was comparable with that of infarction volume (cut-off volume, ≤ 94.87 ml; AUC = 0.821; sensitivity, 90.3%; specificity, 55.6%). Conclusions: Post-treatment DWI ASPECTS might be a potential surrogate of infarction volume and be effective in predicting the clinical outcome of AIS patients after EVT. Key Points: • Post-treatment DWI ASPECTS correlated significantly with infarction volume. • A post-treatment DWI ASPECTS ≥ 6 best predicts good outcomes for AIS patients after EVT. • Post-treatment DWI ASPECTS has the potential in substituting infarction volume in predicting the clinical outcome of AIS patients. [ABSTRACT FROM AUTHOR]

MoS x as a promising electrocatalyst for hydrogen evolution reaction (HER) has the active sites of rims and edges and inert sites of basal plane. A strategy to activate MoS x is to produce more unsaturated S or S vacancies on the inert plane by designing unique nanostructure. Herein, we report a facile electrodeposition assisted by liquid crystal template (LCT) to prepare MoS x film on ITO substrate (MoS x (LCT)). XPS confirms the state of Mo and S of the obtained MoS x film. SEM shows that there are many uniform disk bulges with the diameter of about 100 nm on the surface of MoS x (LCT), which may provide more rims and edges of MoS x . While the electrodeposited MoS x film in water (MoS x (H 2 O)) is a smooth plane structure. The electrochemical measurements show MoS x (LCT) exhibits an ultrahigh activity for HER with the small onsetpotential very close to that of Pt/C, which may be due to not only the uniform disk bulges but also the more unsaturated S atoms of MoS x (LCT). The electrodeposition assisted by LCT may be a novel strategy to prepare novel nanostructure and activate MoS x -based electrocatalysts for HER. [ABSTRACT FROM AUTHOR]

To maximum the activity of transition metal sulfides for hydrogen evolution reaction (HER), two strategies usually have been adopted including designing unique nanostructures and integrating other metal element. Herein, Co x S y /WS 2 nanosheets supported on carbon cloth (Co x S y /WS 2 /CC) have been fabricated via a facile hydrothermal process. The cross-linked structures composed of Co x S y /WS 2 nanosheets uniformly cover on the surface of CC, which may expose abundant active sites for HER and accelerate charge transfer rate. The molar ratio of Co x S y -incorporating has been investigated in detail. The molar ratio of W/Co = 1/3 (noted as Co x S y /WS 2 /CC-3) has been proved to have unique spherical Co x S y /WS 2 nanostructure, which may further expose more active sites for HER. Electrochemical measurements demonstrate that Co x S y -incorporating can enhance HER activity and conductivity compared with WS 2 /CC. In addition, Co x S y /WS 2 /CC-3 exhibits the best HER activity, smallest charge transfer resistance and excellent stability than the counterparts, implying that the degree of Co x S y -incorporating may impact the HER activity of WS 2 . The mechanisms of Co x S y -incorporating on enhancing HER activity of WS 2 have been discussed. It may offer a promising way to design transition metal sulfides-based electrocatalysts for HER by non-precious metal incorporating. [ABSTRACT FROM AUTHOR]

The interwoven WS 2 nanoplates supported on carbon fiber cloth (WS 2 /CFC) have been successfully synthesized by a facile solvothermal process. XRD and XPS confirm the formation of WS 2 /CFC. SEM images show the good dispersion of WS 2 nanoplates with interwoven structures on the surface of CFC. Thanks to the 3D framework of CFC, WS 2 nanoplates realize overall excellent-dispersion interwoven on the surface of CFC compared with pristine bulk WS 2 with severe aggregation. Moreover, CFC not only serves as excellent conductive substrate to accelerate electron transport rate, but also contributes to the close combination between WS 2 and CFC for long-term stability. The electrochemical measurements show that WS 2 /CFC exhibit a high specific capacitance of 399 F g −1 at 1.0 A g −1 , demonstrating the obviously enhanced capability compared with pristine bulk WS 2 . Furthermore, WS 2 /CFC realizes ultra-stable cycling stability with 99% of retention of capacitance after 500 charge-discharge cycles. It may provide novel access of designing carbon-based transition metal disulfides composites for excellent super capacitive properties. [ABSTRACT FROM AUTHOR]

An asymmetric version using imine (VII) gives the product (VIII) with only poor diastereoselectivity. [ABSTRACT FROM AUTHOR]

Background: Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is a grading system to assess the extent and distribution of early ischemic changes. Purpose: To assess inter-rater agreement for total and regional ASPECTS on non-contrast computed tomography (NCCT) images, CT angiography source images (CTA-SI), and CT-perfusion cerebral blood volume (CTP-CBV) maps, and their association with final infarction in patients with acute ischemic stroke (AIS). Material and Methods: A total of 96 consecutive patients with AIS who underwent pre-treatment NCCT and CTP were retrospectively enrolled. CTA-SI was reconstructed using the raw data of CTP. Total and regional ASPECTS were assessed on baseline NCCT, CTA-SI, and CTP-CBV, and on follow-up NCCT or diffusion-weighted imaging. Follow-up ASPECTS served as the reference standard for final infarction. Results: CTP-CBV demonstrated higher concordance for total ASPECTS (interclass correlation coefficient, 0.895 vs. 0.771 vs. 0.777) and regional ASPECTS in internal capsule, lentiform, caudate nuclei, M5 and M6, compared with NCCT and CTA-SI. CTP-CBV showed a trend of stronger correlation with final ASPECTS than NCCT and CTA-SI (0.717 vs. 0.711 vs. 0.565; P > 0.05). ASPECTS in the internal capsule (ρ, 0.756 vs. 0.556; P = 0.016) and caudate nucleus (ρ, 0.717 vs. 0.476; P = 0.010) on CTP-CBV were more strongly correlated with follow-up ASPECTS than NCCT. CTP-CBV showed higher accuracy for predicting final infarction in the internal capsule (92.5% vs. 90.3% and 87.1%; P > 1.000, P = 0.125, respectively) and caudate nucleus (87.1% vs. 79.6% and 77.4%; P = 0.453, P = 0.039, respectively) than CTA-SI and NCCT. Conclusion: CTP-CBV ASPECTS might be more reliable for delineating early ischemic changes and predicting final infarction. [ABSTRACT FROM AUTHOR]

There have been numerous studies concerning the associations of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D), angiotensin II receptor 1 (AT1R) gene A1166C, and endothelial nitric oxide synthase (eNOS) gene 4b/a polymorphisms with risk of pregnancy hypertensive disorders (PHDs). However, the results are inconsistent. A total of 83 eligible studies (10,354/18,446 cases/controls) were included in this meta-analysis. Pooled odds ratios with corresponding 95% confidence intervals were used to calculate these associations. The effects of ethnicity and types of PHDs were also considered. Results showed significant associations between the ACE gene polymorphism and PHDs in all of the populations except that in Africa. The associations also existed in AT1R, eNOS gene polymorphism and PHDs in part of the gene models in the overall population. These results indicated the ACE gene polymorphism was associated with an increased risk of PHDs, whereas the eNOS and AT1R gene polymorphism only have increased susceptibility to PHDs in part of the gene models. [ABSTRACT FROM AUTHOR]

Purpose: To assess the diagnostic accuracy of using Alberta Stroke Program Early Computed Tomography Score (ASPECTS) on CT perfusion (CTP) map to predict a volumetric target mismatch in patients with acute ischemic stroke (AIS). Methods: Three-hundred and seven AIS patients with an onset time within 24h or unclear onset time who underwent CTP evaluation for large vessel occlusion of anterior circulation were enrolled. CTP ASPECTS was evaluated on cerebral blood flow (CBF) and time-to-maximum (Tmax) colored maps, respectively. Automated perfusion analysis software was used to calculate the volumes of ischemic core (volumeCBF<30%) and tissue at risk (volumeTmax>6s). Target mismatch was defined as volumeCBF< 30%<70ml, volumemismatch≥15ml, and volumeTmax >6s/volume CBF< 30%≥1.8. Spearman correlation and receiver operating characteristic curves were used for statistical analyses. Results: Strong correlations were found between CBF ASPECTS and volumeCBF<30%, and between Tmax ASPECTS and volumeTmax>6s for overall population (ρ=−0.872, −0.757) and late-arriving patients (ρ=−0.900, −0.789). Mismatch ASPECTS moderately correlated with mismatch volume for overall population (ρ=0.498) and late-arriving patients (ρ=0.407). A CBF ASPECTS≥5 optimally predicted an ischemic core volume<70ml in overall population (sensitivity, 94.4%; specificity, 80.4%) and late-arriving patients (sensitivity, 89.5%; specificity, 90.5%). A CBF ASPECTS≥6 combined with a Mismatch ASPECTS≥1 optimally identified a target mismatch in overall population (sensitivity, 84.5%; specificity, 77.0%) and late-arriving patients (sensitivity, 83.7%; specificity, 90.0%). Conclusion: CTP ASPECTS might be useful in predicting target mismatch derived from automated perfusion analysis software, and assisting in patient selection for endovascular therapy. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate whether Alberta Stroke Program Early CT Score (ASPECTS) could provide incremental value to collateral score, and their integration could be an effective surrogate of CTP in predicting target mismatch. Material and methods: One hundred and fifty-nine stroke patients (onset time 6–16 h or with unknown onset time) with MCA and/or ICA occlusion underwent non-contrast computed tomography (NCCT) and CT perfusion (CTP) scan for initial assessment. Simulated single-phase CT angiography (sCTA, peak arterial phase) and multiphase CTA (mCTA) were reconstructed from CTP. ASPECTS was assessed on NCCT and sCTA. Collateral score was evaluated on mCTA. Target mismatch was defined as infarct core volume < 70 mL, the mismatch ratio ≥ 1.8, and the absolute mismatch volume ≥ 15 mL. Pearson correlation analysis, Mann–Whitney U test, chi-square test, and receiver operating characteristic curve analyses were performed. Results: Median CTA source image (CTA-SI) ASPECTS was significantly lower than NCCT ASPECTS (p = 0.001). NCCT ASPECTS, CTA-SI ASPECTS, and mCTA collateral score correlated significantly with infarct core volume and mismatch ratio (all p < 0.05). Mismatch group showed significantly higher NCCT ASPECTS, CTA-SI ASPECTS, and mCTA collateral score than non-mismatch group (all p < 0.001). NCCT ASPECTS and CTA-SI ASPECTS showed comparable predicting performance with mCTA collateral score (p > 0.05). Adding CTA-SI ASPECTS to mCTA collateral score improved the performance of mCTA in predicting target mismatch (area under curve, 0.905 vs. 0.804, p = 0.003). Conclusion: ASPECTS can provide incremental information to collateral score in predicting target mismatch. If CTP scan fails, clinical decision based on ASPECTS and collateral score might be reasonable. [ABSTRACT FROM AUTHOR]

Introduction: We aimed to investigate the utility of compressed sensing time-of-flight magnetic resonance angiography (CS TOF-MRA) for diagnosing intracranial and cervical arterial stenosis by using digital subtraction angiography (DSA) as the reference standard.Methods: Thirty-seven patients with head and neck arterial stenoses who underwent CS TOF-MRA and DSA were retrospectively enrolled. The reconstructed resolution of CS TOF-MRA was 0.4 × 0.4 × 0.4 mm3. The scan time was 5 min and 2 s. The image quality of CS TOF-MRA was independently ranked by two neuroradiologists in 1031 arterial segments. The luminal stenosis grades on CS TOF-MRA and DSA were analyzed in 61 arterial segments and were compared using the Wilcoxon signed-rank test. The ability of CS TOF-MRA to predict moderate to severe stenosis or occlusion was analyzed.Results: The image quality of most arterial segments (95.2%) on CS TOF-MRA was excellent. Arterial segments with low image quality were mainly the V3-4 segments of the vertebral artery. The majority of arterial stenoses (62.3%) were located in the cervical internal carotid artery. The luminal stenosis grades of CS TOF-MRA were concordant with that of DSA in 50 of 61 segments (p = 0.366). CS TOF-MRA had a sensitivity of 84.4% and a specificity of 88.5% for predicting moderate to severe stenosis. For detecting occlusion lesions, it had a sensitivity of 100% and a specificity of 94.1%.Conclusion: CS TOF-MRA provides adequate image quality within a reasonable acquisition time and is a reliable tool for diagnosing head and neck arterial steno-occlusive disease.Key Points: • CS TOF-MRA provides a relatively large coverage (16 cm), high resolution (0.4 × 0.4 × 0.4 mm3) and good image quality of head and neck arteries within 5 min and 2 s. • The diagnostic accuracy of CS TOF-MRA in the assessment of moderate to severe stenosis and occlusion was comparable with that of DSA. • Arterial segments with low image quality were mainly the V3 and V4 segments of the vertebral artery. [ABSTRACT FROM AUTHOR]

Background: The application of conventional magnetic resonance imaging (MRI) in glioma grading is limited and non-specific.Purpose: To investigate the application values of MRI, texture analysis (TA) of dynamic contrast-enhanced MRI (DCE-MRI) and intratumoral susceptibility signal (ITSS) on susceptibility weighted imaging (SWI), alone and in combination, for glioma grading.Material and Methods: Fifty-two patients with pathologically confirmed gliomas who underwent DCE-MRI and SWI were enrolled in this retrospective study. Conventional MRIs were evaluated by the VASARI scoring system. TA of DCE-MRI-derived parameters and the degree of ITSS were compared between low-grade gliomas (LGGs) and high-grade gliomas (HGGs). The diagnostic ability of each parameter and their combination for glioma grading were analyzed.Results: Significant statistical differences in VASARI features were observed between LGGs and HGGs ( P < 0.05), of which the enhancement quality had the highest area under the curve (AUC) (0.873) with 93.3% sensitivity and 80% specificity. The TA of DCE-MRI derived parameters were significantly different between LGGs and HGGs ( P < 0.05), of which the uniformity of Ktrans had the highest AUC (0.917) with 93.3% sensitivity and 90% specificity. The degree of ITSS was significantly different between LGGs and HGGs ( P < 0.001). The AUC of the ITSS was 0.925 with 93.3% sensitivity and 90% specificity. The best discriminative power was obtained from a combination of enhancement quality, Ktrans- uniformity, and ITSS, resulting in 96.7% sensitivity, 100.0% specificity, and AUC of 0.993.Conclusion: Combining conventional MRI, TA of DCE-MRI, and ITSS on SWI may help to improve the differentiation between LGGs and HGGs. [ABSTRACT FROM AUTHOR]

Our phosphoproteomics identified that phosphorylation of EphA2 at serine 897 (pS897-EphA2) was significantly upregulated in the high metastatic nasopharyngeal carcinoma (NPC) cells relative to non-metastatic NPC cells. However, the role and underlying mechanism of pS897-EphA2 in cancer metastasis and stem properties maintenance remain poorly understood. In this study, we established NPC cell lines with stable expression of exogenous EphA2 and EphA2-S897A using endogenous EphA2 knockdown cells, and observed that pS897-EphA2 maintained EphA2-dependent NPC cell in vitro migration and invasion, in vivo metastasis and cancer stem properties. Using phospho-kinase antibody array to identify signaling downstream of pS897-EphA2, we found that AKT/Stat3 signaling mediated pS897-EphA2-promoting NPC cell invasion, metastasis and stem properties, and Sox-2 and c-Myc were the effectors of pS897-EphA2. Immunohistochemistry showed that pS897-EphA2 was positively correlated with NPC metastasis and negatively correlated with patient overall survival. Moreover, ERK/RSK signaling controlled serum-induced pS897-EphA2 in NPC cells. Collectively, our results demonstrate that pS897-EphA2 is indispensable for EphA2-dependent NPC cell invasion, metastasis and stem properties by activating AKT/Stat3/Sox-2 and c-Myc signaling pathway, suggesting that pS897-EphA2 can serve as a therapeutic target in NPC and perhaps in other cancers. [ABSTRACT FROM AUTHOR]

In recent years, studies have shown that the secretome of bone marrow mesenchymal stromal cells (BMSCs) contains many growth factors, cytokines, and antioxidants, which may provide novel approaches to treat ischemic diseases. Furthermore, the secretome may be modulated by hypoxic preconditioning. We hypothesized that conditioned medium (CM) derived from BMSCs plays a crucial role in reducing tissue damage and improving neurological recovery after ischemic stroke and that hypoxic preconditioning of BMSCs robustly improves these activities. Rats were subjected to ischemic stroke by middle cerebral artery occlusion and then intravenously administered hypoxic CM, normoxic CM, or Dulbecco modified Eagle medium (DMEM, control). Cytokine antibody arrays and label‐free quantitative proteomics analysis were used to compare the differences between hypoxic CM and normoxic CM. Injection of normoxic CM significantly reduced the infarct area and improved neurological recovery after stroke compared with administering DMEM. These outcomes may be associated with the attenuation of apoptosis and promotion of angiogenesis. Hypoxic preconditioning significantly enhanced these therapeutic effects. Fourteen proteins were significantly increased in hypoxic CM compared with normoxic CM as measured by cytokine arrays. The label‐free quantitative proteomics analysis revealed 163 proteins that were differentially expressed between the two groups, including 107 upregulated proteins and 56 downregulated proteins. Collectively, our results demonstrate that hypoxic CM protected brain tissue from ischemic injury and promoted functional recovery after stroke in rats and that hypoxic CM may be the basis of a potential therapy for stroke patients. Conditioned medium constitutes a therapeutic effect on stroke. Paracrine actions of bone marrow mesenchymal stromal cell are enhanced by hypoxic preconditioning. Apoptosis and neovascularization are involved in this beneficial effect. [ABSTRACT FROM AUTHOR]

The use of mesenchymal stem cells (MSCs) has been reported to improve outcomes in various types of nervous system diseases, primarily based on their neural regenerative differentiation ability and paracrine effect on different neuroprotective cytokines. Genetically modified MSCs may enhance the paracrine effect and may further improve the cell‑based therapeutic outcome of nervous system diseases. Magnetic resonance imaging has been used to monitor distribution and migration of cells labeled with superparamagnetic iron oxide (SPIO) nanoparticles. However, few studies have described the neural differentiation ability of genetically modified and SPIO‑labeled MSCs, which is the foundation for cell tracking and cell therapy in vivo. In this study, canine bone marrow‑derived MSCs (BMSCs) were initially labeled with SPIO, by culturing with 20 μg/ml SPIO for 24 h, and transfected with the brain‑derived neurotrophic factor (BDNF) gene using lentivirus transfection at different multiplicities of infection (MOI) values. The optimized MOI value was demonstrated by cellular viability and enhanced green fluorescent protein (eGFP) rate. Subsequently, the BMSCs were induced to differentiate into neuron‑like cells by chemical induction. The results demonstrated that BDNF‑overexpressing BMSCs labeled with SPIO can be induced into neuron‑like cells with high efficiency and minimal effects on cell viability. Additionally, following neural differentiation, the cells transfected with BDNF and labeled with SPIO expressed significantly higher levels of BDNF and neural markers. The overexpression of BDNF may contribute to neural differentiation of BDNFs, and may have potential benefits for further BMSC‑based therapy in vivo. [ABSTRACT FROM AUTHOR]

Novel vanadium sulfides interwoven nanoflowers supported on nickel foam (VO-S/NF) has been synthesized through a facile two-step access. Firstly, octahedron-structured vanadium oxides as precursor were anchored on the surface of NF (VO/NF) by a hydrothermal process. Secondly, in-situ sulfurization in H 2 S gas has been applied to prepare VO-S/NF. XRD shows that VO-S/NF sample is composed of mixture phases including VS and Ni 3 S 2 , implying the interface effect between VS and Ni 3 S 2 . SEM images demonstrate that octahedron-structured VO from VO/NF changed to VO-S interwoven nanoflowers on VO-S/NF, which are composed of vertical interwoven nanosheets. It can enlarge surface area to expose abundant active sites and facilitate mass and charge transportation. The electrochemical measurements display the enhanced HER activity of VO-S/NF requiring an overpotential of 165 mV to deliver 10 mA cm −2 , which may be ascribed to the novel structure of VS interwoven nanosheets and the synergistic effect between VS and Ni 3 S 2 . Furthermore, VO-S/NF remains high HER activity for at least 10 h with excellent structural stability confirmed by post-HER characterization such as XRD, SEM and XPS. Therefore, it may provide a new way to design multiple transition metal sulfides-based electrocatalysts with unique nanostructure as well as interface effect for HER in alkaline. [ABSTRACT FROM AUTHOR]

The efficiency of electrochemical water splitting is greatly hindered by the thermodynamic uphill reaction of oxygen evolution reaction (OER). Thus, it is important to synthesize an active OER electrocatalysts with abundant active sites, favorable conductivity and good durability. Herein, a facile reduction method using NaBH 4 as readily available reductant has been developed to fabricate the reduced CoFe 2 O 4 nanosheets (NS). The obtained reduced CoFe 2 O 4 NS are rich in oxygen deficient sites, leading to more active sites as well as the enhanced conductivity than the pristine CoFe 2 O 4 hollow nanosphere, which reaches the current density of 10 mA cm −2 at the overpotential of 320 mV in 1 M KOH. Meanwhile, CoFe 2 O 4 samples with three different morphology nanostructures including hollow nanospheres, bulk and nanoparticles have been provided to study the effect of different morphology on NaBH 4 reduction efficiency. As expected, after NaBH 4 reduction, CoFe 2 O 4 hollow nanosphere with relatively higher surface area exhibits most obvious improvement for OER activity and also its corresponding reduced CoFe 2 O 4 NS showed best OER performance than the reduced CoFe 2 O 4 bulk as well as the reduced CoFe 2 O 4 nanoparticles, implying the hollow nanospheres feature more accessible surface area than bulk and nanoparticles samples, thus greatly facilitate efficiency of NaBH 4 reduction treatment. [ABSTRACT FROM AUTHOR]

Oxidized carbon fiber (oCF) as support successfully realizes the vertical growth of uniform WS 2 nanosheets arrays for efficient hydrogen evolution reaction (HER) via a facile hydrothermal process. Thanks to oxygen functional groups on oCF, vertical WS 2 nanosheets structures have grown more easily on oCF, which can provide better dispersion, short charge transfer distance and more exposed active sites for HER in comparison with bulk WS 2 and WS 2 nanosheets on bare carbon fiber (CF) fabricated at the same condition. The electrochemical measurements confirmed that WS 2 /oCF possesses better HER activity than bulk WS 2 and WS 2 /CF. Especially, the 10-h stability with unchanged vertical WS 2 nanosheets morphology further demonstrate the positive effect of oxygen functional groups on the enhanced vertical structure and close combination between WS 2 and oCF. It may offer a facile way to realize more exposed active sites from stable electrocatalyst hybrids of transition metal sulfides by surface oxidization of carbon supports. [ABSTRACT FROM AUTHOR]

This prospective study examined the longitudinal effects of psychological resilience on depression in a Chinese sample of left-behind children. A total of 386 left-behind children completed both a baseline and a 1-year follow-up survey. The prevalence of depression at the baseline and 1-year follow-up was 12.7 and 8.5 per cent, respectively. Multivariate analysis revealed that older age and baseline depressive symptoms were positively associated with follow-up depression, while psychological resilience and quality of life were negatively related to follow-up depression. Our findings provided preliminary evidence that higher psychological resilience was a significantly protective factor of developing depression among left-behind children. [ABSTRACT FROM AUTHOR]

A series of tocopherol-based cationic lipid 3a-3f bearing a pH-sensitive imidazole moiety in the dipeptide headgroup and a reduction-responsive disulfide linkage were designed and synthesized. Acid-base titration of these lipids showed good buffering capacities. The liposomes formed from 3 and co-lipid 1, 2-dioleoyl- sn -glycero-3-phosphocholine (DOPC) could efficiently bind and condense DNA into nanoparticles. Gel binding and HPLC assays confirmed the encapsulated DNA could release from lipoplexes 3 upon addition of 10 mM glutathione (GSH). MTT assays in HEK 293 cells demonstrated that lipoplexes 3 had low cytotoxicity. The in vitro gene transfection studies showed cationic dipeptide headgroups clearly affected the transfection efficiency (TE), and arginine-histidine based dipeptide lipid 3f give the best TE, which was 30.4 times higher than Lipofectamine 3000 in the presence of 10% serum. Cell-uptake assays indicated that basic amino acid containing dipeptide cationic lipids exhibited more efficient cell uptake than serine and aromatic amino acids based dipeptide lipids. Confocal laser scanning microscopy (CLSM) studies corroborated that 3 could efficiently deliver and release DNA into the nuclei of HeLa cells. These results suggest that tocopherol-based dipeptide cationic lipids with pH and reduction dual-sensitive characteristics might be promising non-viral gene delivery vectors. [ABSTRACT FROM AUTHOR]

Novel Ag/SnO 2 has been synthesized by a facile two-step method using hollow SnO 2 nanospheres as support. Firstly, monodispersed SnO 2 hollow nanospheres have been obtained by solvothermal (ethanol/water) method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that hollow SnO 2 nanospheres exhibit good crystalline and monodispersion with the diameter ranging from 200 to 400 nm. Secondly, Ag/SnO 2 nanospheres have been prepared by a facile reduction in silver-ammonia solution. XRD and selected area electron diffraction (SAED) confirm the formation of Ag in Ag/SnO 2 nanospheres. SEM and TEM show the homogeneous coating of Ag nanoparticles on hollow SnO 2 nanospheres. SEM mapping images confirm the uniform distribution of Ag element on SnO 2 nanospheres. The electrocatalytic measurements for hydrazine electro-oxidation have been conducted. The results show that Ag/SnO 2 nanospheres have excellent electrocatalytic activity with −0.12 V (vs. SCE) at the scan rate of 20 mV s −1 . The hollow structure of SnO 2 nanospheres can provide shorter distance of electron transport and better dispersion of Ag nanoparticles, which can be responsible for the enhanced conductivity and efficient utilization of active sites. [ABSTRACT FROM AUTHOR]

A cross-sectional study design was applied amongst a random sample (n = 10158) of Chinese adolescents. Self-completed questionnaires, including demographic characteristics, Internet use situation, Youth Internet Addiction Test, Youth Social Support Rating Scale and Zung Self-rating Depression Scale were utilized to examine the study objectives. Among the study population, the prevalence rate of Internet addiction was 10.4%, with 1038 (10.2%) moderately and 21 (0.2%) severely addicted to the Internet. Results from the multivariate logistic regression analyses suggested that a variety of related factors have significant effects on Internet addiction (parental control, per capita annual household income, academic performance, the access to Internet, online activities). The correlation coefficients showed that Internet addiction was negatively correlated with social support and positively associated with depression. Social support had a significant negative predictive effect on Internet addiction. The mediating effect of depression between social support and Internet addiction was remarkable. [ABSTRACT FROM AUTHOR]

Previous studies examining the possible role of the methylenetetrahydrofolate reductase (MTHFR) polymorphisms in the development of schizophrenia (SZ) and bipolar disorder (BPD) have provided inconclusive findings, this meta-analysis was therefore designed to get a more reliable assessment. A total of 38 articles were identified through a search of electronic databases, up to 27 February 2014. Odds ratios (ORs) with 95 % confidence interval (CIs) were calculated using random effects models. Meta-analysis showed that MTHFR C677T was significantly associated with SZ, the highest OR was found for the recessive model (for TT vs. CT + CC: OR = 1.34, 95 % CI: 1.18-1.53); a marginal association of MTHFR C677T with increased risk of BPD has also been found for the recessive model (OR = 1.26, 95 % CI: 1.00-1.59). Subgroup analysis by ethnicity indicated that the significant association with SZ and BPD existed among Asian and African populations, but not for the white. MTHFR A1298C was significant associated with SZ, the highest OR for the dominant model (OR = 1.13, 95 % CI: 1.03-1.24). Subgroup analysis indicated a significant association with SZ existed in Asian populations, not among the white populations and no significant association was detected between the MTHFR A1298C and BPD in all groups. We conclude that MTHFR polymorphism is associated with SZ and BPD among Asian, African populations, but not the white. [ABSTRACT FROM AUTHOR]

In acute stroke magnetic resonance imaging, many attempts have been made to identify the onset time of ischemic events using the simply quantitative judgment of relative signal intensity (rSI) from various MR images. However, no uniform opinion has been achieved broadly till now. The controversy might derive from the potential patients' selection bias of clinical retrospective study, the discrepant MR parameters, and the various sample sizes among different studies. Thus, we evaluated the temporal change of the relative DWI signal intensity (rDWI), relative ADC value (rADC), relative FLAIR signal intensity (rFLAIR), and relative T2 signal intensity (rT2), and further compare their diagnostic value in identifying the hyperacute lesions based on our embolic canine model with clear onset time. Twenty ischemic models were successfully established. All rSI values were linearly correlated to time with significance until 24 h after model establishment ( P < 0.05). Paired comparison of ROC curves showed that significant difference was found between rADC and other three rSIs ( P < 0.0001). However, no significant difference was found among rDWI, rT2 and rFLAIR. Our results indicated that rDWI, rFLAIR and rT2 may be helpful to predict the onset time of ischemic events with the similar diagnostic value. However, the rADC does not have comparable predictive value in our embolic canine model. [ABSTRACT FROM AUTHOR]