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Background and purposeInitiation of early antiplatelet (EA) therapy after acute ischaemic stroke (AIS) is essential. We aimed to investigate the safety and effectiveness of EA therapy in patients who had an AIS with haemorrhagic infarction (HI) after intravenous thrombolysis (IVT).MethodsBased on a multicentre stroke registry database, patients who had an AIS with post-thrombolysis HI at 24 hours were identified. EA users and non-EA users were defined as patients with HI who received or did not receive antiplatelet therapy between 24 and 48 hours after IVT. Primary outcome was favourable outcome defined as modified Rankin Scale scores 0–2 at 3 months. Secondary outcomes were early neurological deterioration (END) and haemorrhagic transformation expansion.ResultsA total of 842 patients with HI were identified from 24 061 thrombolytic patients within 4.5 hours, and 341 (40.5%) received EA therapy. EA users were more likely to have a favourable outcome (55.7% vs 39.5%, OR 1.565; 95% CI 1.122 to 2.182; p=0.008) and lower rate of END (12.6% vs 21.4%, OR 0.585; 95% CI 0.391 to 0.875; p=0.009) compared with non-EA users. EA therapy was not associated with haemorrhagic transformation expansion (p=0.125). After propensity score matching, EA therapy was still independently associated with favourable outcome (54.3% vs 46.3%, OR 1.495; 95% CI 1.031 to 2.167; p=0.038) and lower risk of END (13.5% vs 21.2%, OR 0.544; 95% CI 0.350 to 0.845; p=0.007).ConclusionsAntiplatelet therapy can be safely used between 24 and 48 hours when HI occurs after IVT, and such therapy is associated with reduced risk of END and improved neurological outcome in patients who had an AIS.

BackgroundScanning electron microscopy (SEM) studies found that the porosity of thrombi might vary among individuals. However, its relationship with the clinical presentation and efficacy of mechanical thrombectomy (MT) remains unknown. We aimed to characterize the ultrastructure of thrombi and explore its association with the complexity of MT and clot perviousness.MethodsSEM was used to observe the morphological features of different components of thrombi obtained from patients with anterior circulation large vessel occlusion undergoing MT and to determine the porosity of thrombi by semi-quantitative analysis. Non-porous thrombi were defined as thrombi with porosity ctp). We assessed the complexity of MT by attempts of retrieval >3 and procedural duration >60 min, defined as the time interval between groin puncture and recanalization.ResultsA total of 49 thrombi were analyzed and 31 (63.3%) were classified as non-porous thrombi. The presence of non-porous thrombi was negatively associated with procedure >60 min (OR 0.152, 95% CI 0.031 to 0.734, p=0.019) and attempts >3 (OR 0.194, 95% CI 0.046 to 0.822, p=0.026) after adjustment. Additionally, receiver operating characteristic curve analysis indicated that TAIctpConclusionsNon-porous thrombi on SEM are easier to be retrieved during MT and could be identified as less pervious clots on CT images.

Evaluation of cerebral perfusion is important for treatment selection in patients with acute large vessel occlusion (LVO). To assess ischemic core and tissue at risk more accurately, we developed a deep learning model named U-net using computed tomography perfusion (CTP) images. A total of 110 acute ischemic stroke patients undergoing endovascular treatment with major reperfusion (≥ 80%) or minimal reperfusion (≤ 20%) were included. Using baseline CTP, we developed two U-net models: one model in major reperfusion group to identify infarct core; the other in minimal reperfusion group to identify tissue at risk. The performance of fixed-thresholding methods was compared with that of U-net models. In the major reperfusion group, the model estimated infarct core with a Dice score coefficient (DSC) of 0.61 and an area under the curve (AUC) of 0.92, while fixed-thresholding methods had a DSC of 0.52. In the minimal reperfusion group, the model estimated tissue at risk with a DSC of 0.67 and an AUC of 0.93, while fixed-thresholding methods had a DSC of 0.51. In both groups, excellent volumetric consistency (intraclass correlation coefficient was 0.951 in major reperfusion and 0.746 in minimal reperfusion) was achieved between the estimated lesion and the actual lesion volume. Thus, in patients with anterior LVO, the CTP-based U-net models were able to identify infarct core and tissue at risk on baseline CTP superior to fixed-thresholding methods, providing individualized prediction of final lesion in patients with different reperfusion patterns.

Animal experiments have demonstrated the dependency of CSF clearance function on age and sleep, which partially underlay the cognitive decline in the elderly. However, evidence is lacking in humans mainly due to limited method to assess CSF clearance function. We aimed to image CSF clearance pathways in human brain by dynamic MRI with intrathecal contrast agent as a CSF tracer. We performed T1-weighted and T2-fluid attenuated inversion recovery imaging with equal sequence parameters before and at multiple time points after intrathecal injection of contrast agent to visualize the putative meningeal lymphatic pathway, peri-olfactory nerve pathway and peri-optic nerve pathway. We defined the CSF clearance function as the percentage change in signal unit ratio of critical locations in these pathways from baseline to 39 hours after intrathecal injection. CSF clearance through the putative meningeal lymphatic and peri-neural pathways were clearly visualized in all 85 patients. The CSF clearance function of meningeal lymphatic and peri-neural pathways were reduced with aging (all P < 0.05). The CSF clearance function through peri-olfactory nerve pathway was positive correlated with sleep quality and cognitive function (both P < 0.05). Moreover, the CSF clearance function through peri-olfactory nerve pathway mediated the association of sleep quality with cognitive function (percent change in β [bootstrap 95% confidence interval]: 35% [−0.220, −0.003]). The study shows promise for dynamic MRI with intrathecal injection of contrast agent as a method to assess CSF clearance function through putative peri-neural pathways, and interprets the impaired clearance through putative peri-olfactory nerve pathway may explain the cognitive decline in patients with dyssomnia.

The poses of robotic endoscopic capsules are indispensable for further follow-up examinations, potential targeted drug delivery, and closed-loop controlling of active locomotion. A novel tracking method using the multiple magnetic excitations with frequency division has been investigated. The multiple excitation coils can simultaneously work at different frequency to improve real-time tracking. A novel model between the magnetic flux density and the capsule's pose has been derived, which shows a nonlinear equation group with multiple local extremum. Then, a Back-Propagation (BP) neural network algorithm combined with the mother wavelet is investigated to solve the pose. To reduce the volume and power consumption, the wireless magnetic sensing module uses digital signal processing as the core framework, which is beneficial to be miniaturized to integrate with the capsule. The functional prototype of the tracking system has been developed, which consists of a wireless magnetic sensing module mounted in the capsule, a magnetic excitation module with frequency division, a wireless receiver and data interface, an excitation coil array and a platform for pose solving. The experimental results show that the mean errors are 0.0098 m in x-component, 0.0122 m in y-component, 0.0077 m in z-component, 0.187 rad in α-component and 0.161 rad in β-component, respectively. The real-time performance of the tracking system is improved.

White matter hyperintensities (WMH) are highly prevalent in older adults and considered to be a contributor to cognition impairment. However, the strategic WMH lesion distribution related to cognitive impairment is still debated. The aim of this study was to characterize the spatial patterns of WMH associated with cognitive impairment and explore its risk factors.We retrospectively analyzed patients who underwent T2 fluid attenuated inversion recovery (FLAIR) and mini-mental state examination (MMSE) in two centers. WHM was classified into four patterns based on T2 FLAIR as follows: (1) multiple subcortical spots (multi-spots); (2) peri-basal ganglia (peri-BG); (3) anterior subcortical patches (anterior SC patches); and (4) posterior subcortical patches (posterior SC patches). We cross-sectionally and longitudinally estimated associations between different WMH patterns and all-cause dementia and cognitive decline. Multivariable logistic regression analysis was followed to identify risk factors of WMH patterns related to cognitive impairment.A total of 442 patients with WMH were enrolled, with average age of 71.6 ± 11.3 years, and MMSE score of 24.1 ± 5.4. Among them, 281 (63.6%), 66 (14.9%), 163 (36.9%) and 197 (44.6%) patients presented multi-spots, peri-BG, anterior SC patches and posterior SC patches, respectively. Patients with anterior SC patches were more likely to have all-cause dementia in cross-sectional study (OR 2.002; 95% CI 1.098-3.649; p = 0.024), and have cognitive decline in longitudinal analysis (OR 3.029; 95% CI 1.270-7.223; p = 0.012). Four patterns of WMH referred to different cognitive domains, and anterior SC patches had the most significant and extensive impact on cognition after Bonferroni multiple comparison correction (all p 0.0125). In addition, older age (OR 1.054; 95% CI 1.027-1.082; p 0.001), hypertension (OR 1.956; 95% CI 1.145-3.341; p = 0.014), higher percentage of neutrophils (OR 1.046; 95% CI 1.014-1.080; p = 0.005) and lower concentration of hemoglobin (OR 0.983; 95% CI 0.967-1.000; p = 0.044) were risk factors for the presence of anterior SC patches.Different patterns of subcortical leukoaraiosis visually identified on MRI might have different impacts on cognitive impairment. Further studies should be undertaken to validate this simple visual classification of WMH in different population.

ObjectivesTo explore the relationship between insufficient ipsilateral cerebral venous drainage and the development of perihematomal edema (PHE) and functional outcome in patients with acute intracerebral hemorrhage (ICH).MethodsWe retrospectively reviewed our prospectively collected database for patients with acute spontaneous supratentorial ICH and analyzed patients who underwent baseline CT perfusion (CTP) within 6 hours of onset and noncontrast CT at 24 hours. Absence of filling of 1 or more of the ipsilateral superficial middle cerebral vein, vein of Trolard, vein of Labbé, basal vein of Rosenthal, and internal cerebral vein, evaluated on venous maps generated from baseline CTP, was identified as absent ipsilateral venous filling (AIVF). Relative PHE (rPHE) was calculated as the ratio of PHE volume to hematoma volume on follow-up CT.ResultsA total of 138 patients were included. Median absolute PHE volume on follow-up CT was 3.5 (1.0–9.3) mL and rPHE was 24.3% (9.0%–49.4%). One absent ipsilateral vein was observed in 38 (27.5%) patients, and 2 absent veins were observed in 5 (3.6%) patients. Multivariate analysis showed that AIVF was independently associated with large rPHE at 24 hours (odds ratio [OR] 4.032, 95% confidence interval [CI] 1.739–9.347, p < 0.001). Large PHE volume was independently associated with poor outcome (OR 1.109, 95% CI 1.009–1.218, p = 0.031).ConclusionAIVF was observed in about one-third of patients with acute ICH, which might be attributed to hypoperfusion after ICH and was strongly related to the development of PHE. Identification of cerebral venous filling status might be a promising imaging marker for PHE and a potential therapeutic target in ICH.

Objective An outbreak of 2019 coronavirus disease (COVID-19) occurred in Wuhan (Hubei, China) in December, 2019. Facing this largescale infectious public health event, everyone is under great psychological pressure. The aim was to investigate the psychological status of people affected by the COVID-19 outbreak in China. Methods The online cross-sectional study involving 922 participants (656 medical staff and 266 general population) was conducted in China between February and March, 2020. The psychological status was evaluated using the Symptom Check List 90 Revised (SCL-90). Linear and logistic regression analysis were used to examine the effect in the study. Results Of the 922 participants, approximately 18.3% had psychological health problems. The score of the SCL-90 was significant higher in medical staff (mean = 1.49) than that in general population (mean = 1.36). In addition, the participants enrolled in March were less likely to have psychological health problems than in February (odds ratio = 0.42, 95% confidence interval [CI] = 0.30 to 0.59). Female had a 1.44-fold risk of psychological health problems than male (95% CI = 1.01 to 2.03). Conclusions In the study, 18.3% had psychological health problems during the outbreak of COVID-19 epidemic. With the remission of the epidemic, the psychological health status of participants has been improved. Medical staff were likely to have higher SCL-90 scores than general population and female had more psychological problems than male. Our findings can be used to formulate psychological interventions for improving the mental health of vulnerable groups during the COVID-19 epidemic., Highlights • The participant in March have less psychological health problems than in February. • Medical staff were likely to have higher SCL-90 scores than general population. • Female was likely to have more psychological health problems than male.

Background and Purpose: This study aimed to investigate whether the application of iodinated contrast agents before intravenous (IV) recombinant tissue plasminogen activator (rt-PA) reduces the efficacy in acute ischemic stroke (AIS) patients. Methods: We analyzed our prospectively collected data of consecutive AIS patients receiving IV rt-PA treatment in the MISSION study. Clinical outcome at 3 months was assessed with modified Rankin Scale (mRS) score and dichotomized into good outcome (0-2) and poor outcome (3-6). Symptomatic intracerebral hemorrhage (sICH) was defined as cerebral hemorrhagic transformation in combination with clinical deterioration of National Institutes of Health Stroke Scale (NIHSS) score ≥4 points at 24-hour. We performed logistic regression analysis and propensity score matching analysis to investigate the impact of iodinated contrast agents before IV rt-PA on poor outcome and sICH, respectively. Results: A total of 3593 patients were finally included and iodinated contrast agents were used before IV rt-PA among 859 (23.9%) patients. Patients in the iodinated contrast group were more likely to result in poor outcome (39.9% vs 33.4%, P=0.001) and sICH (3.4% vs 1.5%, P

OBJECTIVE Aging is a major risk factor for numerous neurological disorders, and the mechanisms underlying brain aging remain elusive. Recent animal studies demonstrated a tight relationship between impairment of the glymphatic pathway, meningeal lymphatic vessels, and aging. However, the relationship in the human brain remains uncertain. METHODS In this observational cohort study, patients underwent magnetic resonance imaging before and at multiple time points after intrathecal administration of a contrast agent. Head T1-weighted imaging was performed to assess the function of the glymphatic pathway and head high-resolution T2-fluid attenuated inversion recovery imaging to visualize putative meningeal lymphatic vessels (pMLVs). We measured the signal unit ratio (SUR) of 6 locations in the glymphatic pathway and pMLVs, defined the percentage change in SUR from baseline to 39 hours as the clearance of the glymphatic pathway and pMLVs, and then analyzed their relationships with aging. RESULTS In all patients (N = 35), the SUR of the glymphatic pathway and pMLVs changed significantly after intrathecal injection of the contrast agent. The clearance of both the glymphatic pathway and pMLVs was related to aging (all p

To establish a reliable, reproducible and accurate release of the drug in the gastrointestinal tract, a novel release mechanism for a controllable drug-delivery system has been investigated. The release mechanism, consisting of a one-way valve for drug release, a drug chamber, two axially magnetized cylindrical permanent magnets and a multi-layer solenoid coil, is hosted in the capsule-shaped shell with diameter 11 mm and length 30 mm. To actuate the coil piston, the two static magnetic fields produced by the two magnets are aligned along the same axis, having the same magnitude, but opposite directions. Based on the principle of the electromagnetic force and the Bernoulli equation, the actuating force can be expressed as a function of the coil stroke and the excitation current, which was modeled and experimentally verified. Thus the actuating force can be controlled by adjusting the activated period and intensity of the coil, resulting in the reproducible release with different doses and mean rates. Then, a prototype of the drug-delivery system has been developed, which consists of a drug-delivery capsule, a radio frequency transmission module, an interface circuit, and an instruction setting and triggering platform. All the drug release parameters, including the release mode, times, dose and mean flow rate, can be set by the platform. The experiment verifies that the drug-delivery capsule can deliver a predetermined dose with different flow rates and dip angles of the capsule. The relative error of the releasing dose becomes larger with increasing releasing rate and decreasing releasing dose.

This paper presents a new dual-rail adiabatic logic which called 2PCDAL. Our proposed circuit is based on 2N2N2P structure. Unlike 2N2N2P which is driven by four-phase clocking, the proposed logic only needs two-phase clocking to operate. Compared with the proposed 2PCDAL and the other dual-rail quasi-adiabatic logic families of cell design, namely, 2N2N2P, CAL, ECRL, PAL, and PFAL, we show that the energy consumption of the proposed 2PCDAL inverter is almost the same as those of the other dual-rail adiabatic logics (i.e. 2N2N2P, ECRL, and PFAL) in the range of from 10 kHz to 10 MHz.