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Background: Despite the well-established potent benefit of mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke, access to MT has not been studied globally. We conducted a worldwide survey of countries on 6 continents to define MT access (MTA), the disparities in MTA, and its determinants on a global scale. Methods: Our survey was conducted in 75 countries through the Mission Thrombectomy 2020+ global network between November 22, 2020, and February 28, 2021. The primary end points were the current annual MTA, MT operator availability, and MT center availability. MTA was defined as the estimated proportion of patients with LVO receiving MT in a given region annually. The availability metrics were defined as ([current MT operators×50/current annual number of estimated thrombectomy-eligible LVOs]×100 = MT operator availability) and ([current MT centers×150/current annual number of estimated thrombectomy-eligible LVOs]×100= MT center availability). The metrics used optimal MT volume per operator as 50 and an optimal MT volume per center as 150. Multivariable-adjusted generalized linear models were used to evaluate factors associated with MTA. Results: We received 887 responses from 67 countries. The median global MTA was 2.79% (interquartile range, 0.70–11.74). MTA was Conclusions: Access to MT on a global level is extremely low, with enormous disparities between countries by income level. The significant determinants of MT access are the country’s per capita gross national income, prehospital LVO triage policy, and MT operator and center availability.

Background: Proton pump inhibitor (PPI) continuous infusions or intermittent boluses are used for the treatment of upper gastrointestinal bleeding (UGIB). Intermittent boluses are easier to give and are of lower cost without affecting clinical outcomes. Objective: To compare the rate of rebleeding between intermittent bolus and continuous infusion PPI therapy. Methods: We performed a retrospective, multicenter review of patients with UGIB receiving either continuous or intermittent PPI therapy. During the study period, due to drug and supply shortages, each institution implemented policies preferring intermittent PPI bolus therapy. We performed bivariate and multivariable comparisons of the 2 treatment strategies, with the primary outcome of interest being incidence of rebleeding. Additional variables of interest included intensive care unit (ICU) and hospital lengths of stay, discharge disposition, and in-hospital mortality. Results: Compared with intermittent bolus dosing (n = 209), patients receiving continuous infusion PPI (n = 237) were associated with a higher rate of rebleeding (33.8% vs 23.0%; P = 0.012); however, no difference was detected in multivariable analysis: adjusted odds ratio, 1.50 (95% confidence interval, 0.91-2.50). There was no difference in median hospital or ICU length of stay, discharge disposition, or in-hospital mortality. Correlatively, patients receiving continuous infusion therapy were more likely to have liver disease (29.1% vs 20.1%; P = 0.028), alcohol use disorder (28.3% vs 16.3.%; P = 0.003), history of lower gastrointestinal bleeding (6.4% vs 1.9%; P = 0.021), variceal bleeding (6.3 vs 2.4%, P = 0.045), and be admitted to the ICU (65.0% vs 32.5%, P = 0.00). Conclusions: Introduction of intermittent PPI bolus UGIB treatment via change in hospital policy was not associated with higher rates of rebleeding. However, continuous PPI therapy may have been perceived as more effective as it was used more commonly in high-risk patients.

We reviewed Clostridioides difficile–positive patients discharged on fidaxomicin after local adoption of 2021 C. difficile infection (CDI) guidelines. From 14 June to 3 October 2021, 80% (12/15) had copayments of $0–$35 and 27% (4/15) required prior authorization. The 30-day CDI recurrence was 7%.

Purpose In light of recently published clinical reports and trials, the TheraSphere Global Dosimetry Steering Committee (DSC) reconvened to review new data and to update previously published clinical and dosimetric recommendations for the treatment of hepatocellular carcinoma (HCC). Methods The TheraSphere Global DSC is comprised of health care providers across multiple disciplines involved in the treatment of HCC with yttrium-90 (Y-90) glass microsphere–based transarterial radioembolization (TARE). Literature published between January 2019 and September 2021 was reviewed, discussed, and adjudicated by the Delphi method. Recommendations included in this updated document incorporate both the results of the literature review and the expert opinion and experience of members of the committee. Results Committee discussion and consensus led to the expansion of recommendations to apply to five common clinical scenarios in patients with HCC to support more individualized efficacious treatment with Y-90 glass microspheres. Existing clinical scenarios were updated to reflect recent developments in dosimetry approaches and broader treatment paradigms evolving for patients presenting with HCC. Conclusion Updated consensus recommendations are provided to guide clinical and dosimetric approaches for the use of Y-90 glass microsphere TARE in HCC, accounting for disease presentation, tumor biology, and treatment intent.

Background and Purpose— Many patients with acute ischemic stroke are not eligible for thrombolysis or mechanical reperfusion therapies due to contraindications, inaccessible vascular occlusions, late presentation, or large infarct core. Sphenopalatine ganglion (SPG) stimulation to enhance collateral flow and stabilize the blood-brain barrier offers an alternative, potentially more widely deliverable, therapy. Methods— In a randomized, sham-controlled, double-masked trial at 41 centers in 7 countries, patients with anterior circulation ischemic stroke not treated with reperfusion therapies within 24 hours of onset were randomly allocated to active SPG stimulation or sham control. The primary efficacy outcome was improvement beyond expectations on the modified Rankin Scale of global disability at 90 days (sliding dichotomy), assessed in the modified intention-to-treat population. The initial planned sample size was 660 patients, but the trial was stopped early when technical improvements in device placement occurred, so that analysis of accumulated experience could be conducted to inform a successor trial. Results— Among 303 enrolled patients, 253 received at least one active SPG or sham stimulation, constituting the modified intention-to-treat population (153 SPG stimulation and 100 sham control). Age was median 73 years (interquartile range, 64–79), 52.6% were female, deficit severity on the National Institutes of Health Stroke Scale was median 11 (interquartile range, 9–15), and time from last known well median 18.6 hours (interquartile range, 14.5–22.5). For the primary outcome, improved 3-month disability beyond expectations, rates in the SPG versus sham treatment groups were 49.7% versus 40.0%; odds ratio, 1.48 (95% CI, 0.89–2.47); P =0.13. A significant treatment interaction with stroke location (cortical versus noncortical) was noted, P =0.04. In the 87 patients with confirmed cortical involvement, rates of improvement beyond expectations were 50.0% versus 27.0%; odds ratio, 2.70 (95% CI, 1.08–6.73); P =0.03. Similar response patterns were observed for all prespecified secondary efficacy outcomes. No differences in mortality or serious adverse event safety end points were observed. Conclusions— SPG stimulation within 24 hours of onset is safe in acute ischemic stroke. SPG stimulation was not shown to statistically significantly improve 3-month disability above expectations, though favorable outcomes were nominally higher with SPG stimulation. Beneficial effects may distinctively be conferred in patients with confirmed cortical involvement. The results of this study need to be confirmed in a larger pivotal study. Clinical Trial Registration— URL: https://www.clinicaltrials.gov . Unique identifier: NCT03767192.

How information is created, shared and consumed has changed rapidly in recent decades, in part thanks to new social platforms and technologies on the web. With ever-larger amounts of unstructured and limited labels, organizing and reconciling information from different sources and modalities is a central challenge in machine learning. This cutting-edge tutorial aims to introduce the multimodal entailment task, which can be useful for detecting semantic alignments when a single modality alone does not suffice for a whole content understanding. Starting with a brief overview of natural language processing, computer vision, structured data and neural graph learning, we lay the foundations for the multimodal sections to follow. We then discuss recent multimodal learning literature covering visual, audio and language streams, and explore case studies focusing on tasks which require fine-grained understanding of visual and linguistic semantics question answering, veracity and hatred classification. Finally, we introduce a new dataset for recognizing multimodal entailment, exploring it in a hands-on collaborative section. Overall, this tutorial gives an overview of multimodal learning, introduces a multimodal entailment dataset, and encourages future research in the topic.

Introduction: In the face of population ageing and contemporary cardiovascular risk factor control, understanding the evolution of ischemic stroke mechanisms may inform stroke prevention strategy and guide resources allocation. Method: Through a registry-based observational study in a regional hospital in Hong Kong, we studied the evolution of stroke mechanisms by TOAST classification over a 15-year period (2004-2018). We retrieved demographic data, pre-defined cardiovascular risks, use of medications, intensity of risk factor control and clinical outcomes (2-year recurrence and 3-month mortality and disability) from the stroke registry. We defined stroke mechanisms by clinical signs and symptoms, cardiovascular risk profile and infarct topography. We compared the trends of stroke mechanisms by Chi-square test for trend and continuous variables by one-way ANOVA test with post-hoc Bonferroni test. Interobserver reliability was assessed by kappa statistics. Results: We included 5982 patients over the 15-year period. The number of atrial fibrillation (AF)-related stroke increased by 213% (p Conclusion: We observed a huge increase in AF-related stroke and newly diagnosed AF at presentation. Our results demanded an enhanced surveillance in detecting AF, primary prevention and thrombectomy facilities given the high morbidity and mortality associated with AF-related strokes. The decline in ICAS-related stroke and its recurrence may underscore the importance of intensive risk factor management in the Asia-Pacific region where ICAS remained prevalent.

AimsPsychiatric hospitals are well equipped to manage patients with complex psychiatric needs, however due to their community setting when a rare medical emergency occurs it is not unusual for a small delay whilst staff search for equipment on the ward or even go to other wards for equipment. The aim of this audit is to ensure that our psychiatric wards in Carseview Centre are well equipped to respond to patients becoming medically unwell and put our nurses and doctors in a position to safely stabilise the patient until furthur help arrives.MethodWe collected data from 3 inpatient adult wards, 1 intensive psychiatric care unit and 1 learning disability unit and compared their resuscitation trolley equipment with local NHS Tayside Emergency Equipment Protocol in January 2020. Following data collection we fed back to the wards about our results and discussions were held between doctors, charge nurses, pharmacists and resuscitation officers to determine whether missing equipment were neccesary in the community setting and to see if there were updates that required for our local protocol to better reflect current practices as it had not been reviewed since 2012. Following multiple meetings we amended our local protocol to better reflect what was . A list of recommendations was also made to improve patient safety.We then collected data again in January 2021ResultFolloing our first data collection we found that the resuscitation trolleys tended to not have ligature packs and masks were generally not by the oxygen cylinders. Hypoglycaemic dextro-tablets were also not readily available. The Learning disability units also did not have an emergency resuscitation trolley.Following our discussions and amendment of the protocol this was finalised in November 2020 and was dissemindated towards the wards and we waited 2 months for the changes to take effects and recollected our data. There continued to be equipment that was incomplete/missing on each individual ward, but none that were consistent throughout the whole hospital site. All the recommendations that were made for the 1st data collection had been done.ConclusionOverall we felt that the emergency trolleys were better equipped in line with the updated protocol compared to the previous audit cycle. The overall pattern of missing equipment was inconsistent and the recommendation was for staff to copmlete checks to address missing/incomplete items when found. Our local protocol also recommends that all ward should stock ‘additional items’ (nebuliser masks and non-rebreather masks), which majority had however were difficult to locate, which could delay patient care.We will continue to repeat data collection cycles and feedback to our wards to ensure patient safety is not compromised.

Polarized epithelia develop distinct cell surface domains, with the apical membrane acquiring characteristic morphological features such as microvilli. Cell polarization is driven by polarity determinants including the evolutionarily conserved partitioning-defective (PAR) proteins that are separated into distinct cortical domains. PAR protein segregation is thought to be a consequence of asymmetric actomyosin contractions. The mechanism of activation of apically polarized actomyosin contractility is unknown. Here we show that the Cdc42 effector MRCK activates myosin-II at the apical pole to segregate aPKC-Par6 from junctional Par3, defining the apical domain. Apically polarized MRCK-activated actomyosin contractility is reinforced by cooperation with aPKC-Par6 downregulating antagonistic RhoA-driven junctional actomyosin contractility, and drives polarization of cytosolic brush border determinants and apical morphogenesis. MRCK-activated polarized actomyosin contractility is required for apical differentiation and morphogenesis in vertebrate epithelia and Drosophila photoreceptors. Our results identify an apical origin of actomyosin-driven morphogenesis that couples cytoskeletal reorganization to PAR polarity signalling.

Background Behavioral dysexecutive syndrome ( BDES ) is a common phenomenon following stroke. To date, research has focused mainly on individual behavioral symptoms rather than a more comprehensive characterization of goal‐directed behavior in stroke survivors. This cross‐sectional study evaluated the prevalence and clinical correlates of BDES in Hong Kong stroke survivors. Methods and Results A total of 369 stroke survivors were recruited from a regional hospital at 3 months after their index stroke. Patients’ demographic and clinical characteristics were extracted from a comprehensive stroke database. BDES was measured with the Chinese version of the Dysexecutive Questionnaire. Four neurocognitive batteries assessed domains of cognitive executive functions. The prevalence of BDES 3 months poststroke was 18.7%. At that time point, the Hospital Anxiety Depression Scale and Mini‐Mental State Examination scores and the presence of depression were significant predictors of BDES in a multivariate logistic regression analysis. These parameters remained significant predictors of the Dysexecutive Questionnaire score in a linear stepwise regression analysis and together accounted for 28.5% of the variance. Current depression was predictive of the Dysexecutive Questionnaire score in patients with BDES , with a variance of 9.7%. Furthermore, compared with the non‐ BDES group, patients with BDES exhibited poor performance‐based executive function in the Chinese version of the Frontal Assessment Battery and color trails, arrow, and category fluency tests. Conclusions Symptoms of anxiety, current depression, and global cognitive function may be independent predictors of the presence and severity of BDES 3 months poststroke. Stroke survivors with BDES exhibit poor executive functioning, including goal maintenance and semantic memory.

Summary Mammalian cell cytoskeletal reorganization for efficient directional movement requires tight coordination of actomyosin and microtubule networks. In this study, we show that LRAP35a potentiates microtubule stabilization by promoting CLASP2/EB1 interaction besides its complex formation with MRCK/MYO18A for retrograde actin flow. The alternate regulation of these two networks by LRAP35a is tightly regulated by a series of phosphorylation events that dictated its specificity. Sequential phosphorylation of LRAP35a by Protein Kinase A (PKA) and Glycogen Synthase Kinase-3β (GSK3β) initiates the association of LRAP35a with CLASP2, while subsequent binding and further phosphorylation by Casein Kinase 1δ (CK1δ) induce their dissociation, which facilitates LRAP35a/MRCK association in driving lamellar actomyosin flow. Importantly, microtubule dynamics is directly moderated by CK1δ activity on CLASP2 to regulate GSK3β phosphorylation of the SxIP motifs that blocks EB1 binding, an event countered by LRAP35a interaction and its competition for CK1δ activity. Overall this study reveals an essential role for LRAP35a in coordinating lamellar contractility and microtubule polarization in cell migration.

Summary Background Previous randomised trials have shown an overwhelming benefit of mechanical thrombectomy for treating patients with stroke caused by large vessel occlusion of the anterior circulation. Whether endovascular treatment is beneficial for vertebrobasilar artery occlusion remains unknown. In this study, we aimed to investigate the safety and efficacy of endovascular treatment of acute strokes due to vertebrobasilar artery occlusion. Methods We did a multicentre, randomised, open-label trial, with blinded outcome assessment of thrombectomy in patients presenting within 8 h of vertebrobasilar occlusion at 28 centres in China. Patients were randomly assigned (1:1) to endovascular therapy plus standard medical therapy (intervention group) or standard medical therapy alone (control group). The randomisation sequence was computer-generated and stratified by participating centres. Allocation concealment was implemented by use of sealed envelopes. The primary outcome was a modified Rankin scale (mRS) score of 3 or lower (indicating ability to walk unassisted) at 90 days, assessed on an intention-to-treat basis. The primary safety outcome was mortality at 90 days. Secondary safety endpoints included the rates of symptomatic intracranial haemorrhage, device-related complications, and other severe adverse events. The BEST trial is registered with ClinicalTrials.gov , NCT02441556 . Findings Between April 27, 2015, and Sept 27, 2017, we assessed 288 patients for eligibility. The trial was terminated early after 131 patients had been randomly assigned (66 patients to the intervention group and 65 to the control group) because of high crossover rate and poor recruitment. In the intention-to-treat analysis, there was no evidence of a difference in the proportion of participants with mRS 0–3 at 90 days according to treatment (28 [42%] of 66 patients in the intervention group vs 21 [32%] of 65 in the control group; adjusted odds ratio [OR] 1·74, 95% CI 0·81–3·74). Secondary prespecified analyses of the primary outcome, done to assess the effect of crossovers, showed higher rates of mRS 0–3 at 90 days in patients who actually received the intervention compared with those who received standard medical therapy alone in both per-protocol (28 [44%] of 63 patients with intervention vs 13 [25%] of 51 with standard therapy; adjusted OR 2·90, 95% CI 1·20–7·03) and as-treated (36 [47%] of 77 patients with intervention vs 13 [24%] of 54 with standard therapy; 3·02, 1·31–7·00) populations. The 90-day mortality was similar between groups (22 [33%] of 66 patients in the intervention vs 25 [38%] of 65 in the control group; p=0·54) despite a numerically higher prevalence of symptomatic intracranial haemorrhage in the intervention group. Interpretation There was no evidence of a difference in favourable outcomes of patients receiving endovascular therapy compared with those receiving standard medical therapy alone. Results might have been confounded by loss of equipoise over the course of the trial, resulting in poor adherence to the assigned study treatment and a reduced sample size due to the early termination of the study. Funding Jiangsu Provincial Special Program of Medical Science.

Fine-grained recognition distinguishes among categories with subtle visual differences. In order to differentiate between these challenging visual categories, it is helpful to leverage additional information. Geolocation is a rich source of additional information that can be used to improve fine-grained classification accuracy, but has been understudied. Our contributions to this field are twofold. First, to the best of our knowledge, this is the first paper which systematically examined various ways of incorporating geolocation information into fine-grained image classification through the use of geolocation priors, post-processing or feature modulation. Secondly, to overcome the situation where no fine-grained dataset has complete geolocation information, we release two fine-grained datasets with geolocation by providing complementary information to existing popular datasets - iNaturalist and YFCC100M. By leveraging geolocation information we improve top-1 accuracy in iNaturalist from 70.1% to 79.0% for a strong baseline image-only model. Comparing several models, we found that best performance was achieved by a post-processing model that consumed the output of the image-only baseline alongside geolocation. However, for a resource-constrained model (MobileNetV2), performance was better with a feature modulation model that trains jointly over pixels and geolocation: accuracy increased from 59.6% to 72.2%. Our work makes a strong case for incorporating geolocation information in fine-grained recognition models for both server and on-device., Comment: ICCVW 2019

Mammalian cell cytoskeletal reorganization for efficient directional movement requires tight coordination of actomyosin and microtubule networks. Here we show that LRAP35a potentiated microtubule stabilization by promoting CLASP2/EB1 interaction besides MRCK/MYO18A complex formation for retrograde actin flow. The alternate regulation of these two networks by LRAP35a was tightly regulated by a series of phosphorylation events that dictated its specificity. Sequential phosphorylation of LRAP35a by PKA and GSK3β initiated the association of LRAP35a with CLASP2, while subsequent binding and further phosphorylation by CK1δ induced their dissociation which would facilitate LRAP35a/MRCK association in driving lamellar actomyosin flow. Importantly, microtubule dynamics was directly moderated by CK1δ activity on CLASP2 to regulate GSK3β phosphorylation of the SxIP motifs that block EB1 binding, an event countered by LRAP35a interaction and its competition for CK1δ activity. This study thus reveals an essential role for LRAP35a in coordinating lamellar contractility and microtubule polarization in cell migration.

Background and Purpose: Vasa vasorum, which constitutes a network of microvasculature, plays a nutritive and drainable role in vessel walls of arteries. The existence of vasa vasorum within brain vasculature is rarely reported. Based on a series of cerebral artery specimens, we aimed to describe the distribution features of vasa vasorum among intracranial arteries, including middle cerebral arteries (MCAs), basilar arteries (BAs) and vertebral arteries (VAs) and potential effects of vasa vasorum on atherosclerosis morphology. Methods: One hundred and fifty- seven arteries (64 MCAs, 32 Bas and 61 VAs) were obtained from consecutively recruited 32 autopsy cases aged 45 years or above. Routine histology and immunostaining processing were performed to identify the presence of adventitial vasa vasorum and to study the phenotypes and specific components of intracranial atherosclerotic lesions. Results: Among 157 intracranial cerebral arteries, adventitial vasa vasorum were present most frequently in the vertebral arteries (77%), followed by basilar arteries (44%) and middle cerebral arteries (20%). Arteries with adventitial vasa vasorum had greater thickness of tunica adventitia (0.10±0.06 mm vs. 0.06±0.03 mm, p &lt 0.001) and larger size in diameters (3.41± 0.73 mm vs. 2.97± 0.66 mm, p &lt 0.001). The occurrence of adventitial vasa vasorum correlated with high frequency of complicated plaques and higher rate of concentric atherosclerotic lesions (70% vs. 36%, p &lt 0.001). Conclusion: For the first time, our study demonstrated the presence of adventitial vasa vasorum within brain vasculature, especially at vertebral arteries. The correlations between adventitial vasa vasorum and intraplaque hemorrhage, inflammation and calcification suggest that adventitial vasa vasorum may serve as a predictor of unstable atherosclerotic lesions. Further studies are required to explore the biological behavior of adventitial vasa vasorum within cerebral arteries.

We address the problem of distance metric learning (DML), defined as learning a distance consistent with a notion of semantic similarity. Traditionally, for this problem supervision is expressed in the form of sets of points that follow an ordinal relationship -- an anchor point $x$ is similar to a set of positive points $Y$, and dissimilar to a set of negative points $Z$, and a loss defined over these distances is minimized. While the specifics of the optimization differ, in this work we collectively call this type of supervision Triplets and all methods that follow this pattern Triplet-Based methods. These methods are challenging to optimize. A main issue is the need for finding informative triplets, which is usually achieved by a variety of tricks such as increasing the batch size, hard or semi-hard triplet mining, etc. Even with these tricks, the convergence rate of such methods is slow. In this paper we propose to optimize the triplet loss on a different space of triplets, consisting of an anchor data point and similar and dissimilar proxy points which are learned as well. These proxies approximate the original data points, so that a triplet loss over the proxies is a tight upper bound of the original loss. This proxy-based loss is empirically better behaved. As a result, the proxy-loss improves on state-of-art results for three standard zero-shot learning datasets, by up to 15% points, while converging three times as fast as other triplet-based losses., To be presented in ICCV 2017

Myotonic dystrophy kinase-related Cdc42-binding kinase (MRCK) has been shown to localize to the lamella of mammalian cells through its interaction with an adaptor protein, leucine repeat adaptor protein 35a (LRAP35a), which links it with myosin 18A (MYO18A) for activation of the lamellar actomyosin network essential for cell migration. Here, we report the identification of another adaptor protein LRAP25 that mediates MRCK association with LIM kinase 1 (LIMK1). The lamellipodium-localized LRAP25-MRCK complex is essential for the regulation of local LIMK1 and its downstream F-actin regulatory factor cofilin. Functionally, inhibition of either MRCK or LRAP25 resulted in a marked suppression of LIMK1 activity and down-regulation of cofilin phosphorylation in response to aluminum fluoride induction in B16-F1 cells, which eventually resulted in deregulation of lamellipodial F-actin and reorganization of cytoskeletal structures causing defects in cell polarization and motility. These biochemical and functional characterizations thus underline the functional relevance of the LRAP25-MRCK complex in LIMK1-cofilin signaling and the importance of LRAP adaptors as key determinants of MRCK cellular localization and downstream specificities.

Background and Purpose— Geographic variation and sex difference in the distribution of intracranial atherosclerosis (ICAS) have not been fully discussed before in Chinese patients with cerebral ischemia. We performed this study with the aim to investigate geographic and sex difference in the distribution of ICAS in China. Methods— In this prospective multicenter study, we evaluated 2864 consecutive patients who experienced an acute cerebral ischemia within 7 days of symptom onset in 22 hospitals in China. All the inclusive patients underwent 3-dimensional time-of-flight MR angiography and duplex color Doppler ultrasound or contrast-enhanced MR angiography to document the presence of intracranial or extracranial stenosis. Intracranial large-artery atherosclerosis was defined as ≥50% diameter reduction on MR angiography. Results— The proportion of patients with ICAS was significantly higher in north China than in south China (50.22% versus 41.88%; P 63 years, the percentage of ICAS in women was notably higher than in men (51.51% versus 45.40%; P =0.028). In elderly patients, women had higher proportion of diabetes mellitus, hypertension, hyperlipidemia, and heart disease than men. Conclusions— There exists geographic and sex difference in the distribution of symptomatic ICAS in China. Public health measures should strengthen improving social determinants of health and risk factor prevention/control in high-risk populations for decreasing stroke risk.

Focal adhesions are protein complexes that link metazoan cells to the extracellular matrix through the integrin family of transmembrane proteins. Integrins recruit many proteins to these complexes, referred to as the "adhesome." We used proximity-dependent biotinylation (BioID) in U2OS osteosarcoma cells to label proteins within 15 to 25 nm of paxillin, a cytoplasmic focal adhesion protein, and kindlin-2, which directly binds β integrins. Using mass spectrometry analysis of the biotinylated proteins, we identified 27 known adhesome proteins and 8 previously unknown components close to paxillin. However, only seven of these proteins interacted directly with paxillin, one of which was the adaptor protein Kank2. The proteins in proximity to β integrin included 15 of the adhesion proteins identified in the paxillin BioID data set. BioID also correctly established kindlin-2 as a cell-cell junction protein. By focusing on this smaller data set, new partners for kindlin-2 were found, namely, the endocytosis-promoting proteins liprin β1 and EFR3A, but, contrary to previous reports, not the filamin-binding protein migfilin. A model adhesome based on both data sets suggests that focal adhesions contain fewer components than previously suspected and that paxillin lies away from the plasma membrane. These data not only illustrate the power of using BioID and stable isotope-labeled mass spectrometry to define macromolecular complexes but also enable the correct identification of therapeutic targets within the adhesome.

Introduction: For successful telestroke through the “hub-and-spoke model”, availability of neurologists 24-hour daily in hub hospitals is pivotal for immediate treatment advice. Unfortunately, this luxury is not available in Hong Kong due to shortage of neurologists. To facilitate 24-hour thrombolysis service in Hong Kong, we provide telestroke support with a different model. During non-working hours, when no on-site neurologist is available, patients are evaluated by off-site neurologists through mobile teleconsultation with iPads. On contrary to hub-and-spoke model, where teleconsultations are conducted within the hospital under stable network with direct access to electronic patient records, we perform teleconsultations with iPads outside the hospital where mobile network is location-dependent and access to electronic record is indirectly through a firewalled hospital network. Hypothesis & Objectives: The objective of this study is to evaluate the feasibility and safety of this telestroke model. Methods: We recruited 118 consecutive patients evaluated by off-site mobile telestroke for thrombolysis triage in Prince of Wales Hospital during the period from May 2012 to November 2014. Results: Technical problems were encountered in 27 patients (22.8%), including failure to access CT brain images in 13 cases, which required use of backup teleradiology system. Nevertheless, since the implementation of telestroke, the number of patients who received thrombolysis has increased by > 3-fold. Seventy-eight patients received thrombolysis through telestroke, and had outcome comparable to 84 patients thrombolysed by on-site neurologists. Favorable outcome at 3 months (mRS 0-1) were 46.2% in telestroke group vs 45.2% in on-site group, p = 0.907. Symptomatic intracerebral hemorrhage and mortality were similar between the two groups. Conclusion: Technical problems are common with off-site teleconsultations in the initial implementation of telestroke, that backup teleradiology system is essential. In Hong Kong where mobile network broadly covers most areas in the city, telestroke through off-site mobile teleconsultation with iPad is feasible, safe and significantly facilitates the implementation of 24-hour thrombolysis service.

Background: Intracranial arterial stenosis (ICAS) is a predominant cause of ischemic stroke in Asia. Changes of the signal intensities across ICAS lesions on time-of-flight magnetic resonance angiography (MRA) have been indicated to partially reflect the hemodynamic significance of the lesions, which we aimed to verify by correlating with cerebral perfusion features provided by CT perfusion imaging. Methods: Ischemic stroke or transient ischemic attack patients with unilateral symptomatic stenosis (≥50%) of intracranial internal carotid artery or middle cerebral artery were included in this study. Change of signal intensities across an ICAS lesion on time-of-flight MRA was calculated by the distal and proximal signal intensity ratio (SIR). Cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) within the middle cerebral artery territory of ipsilateral and contralateral hemispheres were evaluated on the CT perfusion images at the basal ganglia level. Relative CBV, CBF and MTT were defined as the ratios of the parameters obtained from ipsilateral and contralateral hemispheres. The relationships between SIR and CT perfusion parameters were analyzed. Results: Fifty subjects (74% male, mean age 62.84) were recruited. Overall, mean SIR was 0.77 ± 0.17. SIR of ICAS significantly, linearly and negatively correlated with ipsilateral CBV (r = -0.335, P = 0.017), CBF (r = -0.312, P = 0.028), and MTT (r = -0.301, P = 0.034), and relative MTT (r = -0.443, P = 0.001). Conclusions: Changes of the signal intensities across ICAS lesions on time-of-flight MRA may be a simple marker to reflect cerebral perfusion changes in patients with symptomatic ICAS.

Cell movement requires forces generated by non-muscle myosin II (NM II) for coordinated protrusion and retraction. The Cdc42/Rac effector MRCK regulates a specific actomyosin network in the lamella essential for cell protrusion and migration. Together with the Rho effector ROK required for cell rear retraction, they cooperatively regulate cell motility and tumour cell invasion. Despite the increasing importance of ROK inhibitors for both experimental and clinical purposes, there is a lack of specific inhibitors for other related kinases such as MRCK. Here, we report the identification of chelerythrine chloride as a specific MRCK inhibitor. Its ability to block cellular activity of MRCK resulted in the specific loss of NM II-associated MLC phosphorylation in the lamella, and the consequential suppression of cell migration.Structured summary of protein interactionsDMPK phosphorylates MYPT by protein kinase assay (View interaction)PAK alpha phosphorylates MLC by protein kinase assay (View interaction)MRCK alpha phosphorylates MLC by protein kinase assay (View interaction)CRIK phosphorylates MLC by protein kinase assay (View interaction)MRCK beta phosphorylates MLC by protein kinase assay (View interaction)ROK alpha phosphorylates MLC by protein kinase assay (View Interaction 1, 2)MRCK beta phosphorylates MYPT by protein kinase assay (View interaction)MRCK alpha phosphorylates MYPT by protein kinase assay (View interaction)ROK alpha phosphorylates MYPT by protein kinase assay (View interaction)MLCK phosphorylates MLC by protein kinase assay (View interaction)

A novel strategy for the development of molecular aptamer beacon for a signal transduction protein, myotonic dystrophy kinase-related Cdc42-binding kinase (MRCK) was proposed in this work. MRCK is an important downstream effector protein of Cdc42 that phosphorylates proteins involved in organizing actin structures responsible for forming stress fibres, lamellipodia or filopodia. The simple method for MAB design could potentially be applied to other aptamers for modification into a protein probe. The MRCK aptamer was modified into a MAB by adding nucleotides on the 5′ end, which are complementary to the 3′ end of the aptamer so as to destroy the existing structure and change it into a MB form. In the absence of MRCK, the MAB remained a hairpin structure. However, in the presence of MRCK, the equilibrium was shifted towards the formation of the MRCK-aptamer complex, resulting in the preference for the MRCK-binding conformer, where a fluorescence-quenching pair added to the 5′ and 3′ ends signaled any protein-dependent conformation change. The development of MABs for signal transduction proteins will have the potential to replace antibodies for diagnostic assays as well as protein studies in cellular imaging.

Intracellular calcium influx through NMDA receptors triggers a cascade of deleterious signaling events which lead to neuronal death in neurological conditions such as stroke. However, it is not clear as to the molecular mechanism underlying early damage response from axons and dendrites which are important in maintaining a network essential for the survival of neurons. Here, we examined changes of axons treated with glutamate and showed the appearance of betaIII-tubulin positive varicosities on axons before the appearance of neuronal death. Dizocilpine blocked the occurrence of varicosities on axons suggesting that these microstructures were mediated by NMDA receptor activities. Despite early increased expression of pCaMKII and pMAPK after just 10 min of glutamate treatment, only inhibitors to Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and calpain prevented the occurrence of axonal varicosities. In contrast, inhibitors to Rho kinase, mitogen-activated protein kinase and phosphoinositide 3-kinase were not effective, nor were they able to rescue neurons from death, suggesting CaMKII and calpain are important in axon survival. Activated CaMKII directly phosphorylates collapsin response mediator protein (CRMP) 2 which is independent of calpain-mediated cleavage of CRMP2. Over-expression of CRMP2, but not the phosphorylation-resistant mutant CRMP2-T555A, increased axonal resistance to glutamate toxicity with reduced numbers of varicosities. The levels of both pCRMP2 and pCaMKII were also increased robustly within early time points in ischemic brains and which correlated with the appearance of axonal varicosities in the ischemic neurons. Collectively, these studies demonstrated an important role for CaMKII in modulating the integrity of axons through CRMP2 during excitotoxicity-induced neuronal death.

The mechanism by which Raf-1 antagonizes Rok-α to promote migration and tumorigenesis is revealed., The activity of Raf-1 and Rok-α kinases is regulated by intramolecular binding of the regulatory region to the kinase domain. Autoinhibition is relieved upon binding to the small guanosine triphosphatases Ras and Rho. Downstream of Ras, Raf-1 promotes migration and tumorigenesis by antagonizing Rok-α, but the underlying mechanism is unknown. In this study, we show that Rok-α inhibition by Raf-1 relies on an intermolecular interaction between the Rok-α kinase domain and the cysteine-rich Raf-1 regulatory domain (Raf-1reg), which is similar to Rok-α's own autoinhibitory region. Thus, Raf-1 mediates Rok-α inhibition in trans, which is a new concept in kinase regulation. This mechanism is physiologically relevant because Raf-1reg is sufficient to rescue all Rok-α–dependent defects of Raf-1–deficient cells. Downstream of Ras and Rho, the Raf-1–Rok-α interaction represents a novel paradigm of pathway cross talk that contributes to tumorigenesis and cell motility.

SummaryActomyosin retrograde flow underlies the contraction essential for cell motility. Retrograde flow in both lamellipodia and lamella is required for membrane protrusion and for force generation by coupling to cell adhesion. We report that the Rac/Cdc42-binding kinase MRCK and myosin II-related MYO18A linked by the adaptor protein LRAP35a form a functional tripartite complex, which is responsible for the assembly of lamellar actomyosin bundles and of a subnuclear actomyosin network. LRAP35a binds independently to MYO18A and MRCK. This binding leads to MRCK activation and its phosphorylation of MYO18A, independently of ROK and MLCK. The MRCK complex moves in concert with the retrograde flow of actomyosin bundles, with MRCK being able to influence other flow components such as MYO2A. The promotion of persistent protrusive activity and inhibition of cell motility by the respective expression of wild-type and dominant-negative mutant components of the MRCK complex show it to be crucial to cell protrusion and migration.