Dynamic physiological α-synuclein S129 phosphorylation is driven by neuronal activity.

In Parkinson's disease and other synucleinopathies, the elevation of α-synuclein phosphorylated at Serine129 (pS129) is a widely cited marker of pathology. However, the physiological role for pS129 has remained undefined. Here we use multiple approaches to show for the first time that pS129 functions as a physiological regulator of neuronal activity. Neuronal activity triggers a sustained increase of pS129 in cultured neurons (200% within 4 h). In accord, brain pS129 is elevated in environmentally enriched mice exhibiting enhanced long-term potentiation. Activity-dependent α-synuclein phosphorylation is S129-specific, reversible, confers no cytotoxicity, and accumulates at synapsin-containing presynaptic boutons. Mechanistically, our findings are consistent with a model in which neuronal stimulation enhances Plk2 kinase activity via a calcium/calcineurin pathway to counteract PP2A phosphatase activity for efficient phosphorylation of membrane-bound α-synuclein. Patch clamping of rat SNCA-/- neurons expressing exogenous wild-type or phospho-incompetent (S129A) α-synuclein suggests that pS129 fine-tunes the balance between excitatory and inhibitory neuronal currents. Consistently, our novel S129A knock-in (S129AKI) mice exhibit impaired hippocampal plasticity. The discovery of a key physiological function for pS129 has implications for understanding the role of α-synuclein in neurotransmission and adds nuance to the interpretation of pS129 as a synucleinopathy biomarker.

Impact of leukoaraiosis in patients with acute ischemic stroke treated with thrombectomy: a post hoc analysis of the DIRECT-MT trial.

BACKGROUND: The influence of leukoaraiosis in patients with acute ischemic stroke (AIS) given intra-arterial treatment (IAT) with or without preceding intravenous thrombolysis (IVT) remains unknown. OBJECTIVE: To assess the clinical and radiological outcomes of IAT in patients with or without leukoaraiosis. METHODS: Patients of the direct mechanical thrombectomy trial (DIRECT-MT) whose leukoaraiosis grade could be assessed were included. DIRECT-MT was a randomized clinical trial performed in China to assess the effect of direct IAT compared with intravenous thrombolysis plus IAT. We employed the Age-Related White Matter Changes Scale for grading leukoaraiosis (ARWMC, 0 indicates no leukoaraiosis, 1-2 indicates mild-to-moderate leukoaraiosis, and 3 indicates severe leukoaraiosis) based on brain CT. The primary outcome was the score on the modified Rankin Scale (mRS) assessed at 90 days. RESULTS: There were 656 patients in the trial, 649 patients who were included, with 432 patients without leukoaraiosis, and 217 (33.4%) patients with leukoaraiosis divided into mild-to-moderate (n=139) and severe groups (n=78). Leukoaraiosis was a predictor of a worse mRS score (adjusted OR (aOR)=0.7 (95% CI 0.5 to 0.8)) and higher mortality (aOR=1.4 (1.1 to 1.9)), but it was not associated with symptomatic intracranial hemorrhage (sICH) (aOR=0.9 (0.5 to 1.5)). IVT preceding IAT did not increase sICH risk for patients with no (aOR=1.4 (0.6 to 3.4)), mild-to-moderate (aOR=1.5 (0.3 to 7.8)), or severe (aOR=1.5 (0.1 to 21.3)) leukoaraiosis. CONCLUSION: Patients with leukoaraiosis with AIS due to large vessel occlusion are at increased risk of a poor functional outcome after IAT but demonstrate similar sICH rates, and IVT preceding IAT does not increase the risk of sICH in Chinese patients with leukoaraiosis.

Predictors of futile recanalization in basilar artery occlusion patients undergoing endovascular treatment: a post hoc analysis of the ATTENTION trial.

Background: Few studies have focused on factors associated with futile recanalization in patients with an acute basilar artery occlusion (BAO) that was treated with modern endovascular therapy (EVT). The aim of this study was to explore the factors associated with futile recanalization in patients with an acute BAO presented within 12 h. Methods: This is a post-hoc analysis of the ATTENTION trial (The Trial of Endovascular Treatment of Acute Basilar-Artery Occlusion, ClinicalTrials.gov, number NCT04751708). Demographics, clinical characteristics, acute stroke workflow interval times, and imaging characteristics were compared between the futile recanalization and favorable recanalization groups. The favorable outcome was defined as a modified Rankin scale (mRS) score of 0-3 at 90 days, successful reperfusion was defined as thrombolysis in cerebral infarction (TICI) 2b and 3 on the final angiogram, and futile recanalization was defined as failure to achieve a favorable outcome despite successful reperfusion. A multivariate analysis was performed to identify the predictors of futile recanalization. Results: In total, 185 patients were included in the final analysis: 89 (48.1%) patients had futile recanalization and 96 (51.9%) patients had favorable recanalization. In the multivariable logistic regression analysis, older age (OR 1.04, 95% CI 1.01 to 1.08, p = 0.01) and diabetes mellitus (OR 3.35, 95% CI 1.40 to 8.01, p = 0.007) were independent predictors of futile recanalization. Conclusion: Futile recanalization occurred in nearly half of patients with acute BAO following endovascular treatment. Old age and diabetes mellitus were identified as independent predictors of futile recanalization after endovascular therapy for acute BAO.

Application of Balloon AngioplaSty with the dIstal protection of Stent Retriever (BASIS) technique for acute intracranial artery atherosclerosis-related occlusion.

Background: Endovascular therapy (EVT) is complex in the context of intracranial atherosclerosis (ICAS)-related large vessel occlusion (LVO) and the re-occlusion rates are high due to residual stenosis, the procedure time is long and the optimal EVT technique is unclear. The Balloon AngioplaSty with the dIstal protection of Stent Retriever (BASIS) technique is a novel thrombectomy technique that allows emergent balloon angioplasty to be performed via the wire of the retrieval stent. Our study presents our initial experience with the BASIS technique in ICAS-related LVO and assesses its feasibility. Method: In patients with ICAS-related LVO treated with BASIS, clinical and angiographic data were retrospectively analyzed. Angiographic data included first-pass reperfusion (PFR), the rate of residual stenosis, distal emboli, and re-occlusion post-procedure. The Extended Thrombolysis in Cerebral Infarction (eTICI) scale was used to assess reperfusion extent, and an eTICI score ≥2b was defined as successful perfusion. Clinical outcome was evaluated at 3 months (modified Rankin score [mRS]), and an mRS ≤ 2 was defined as a good clinical outcome. Results: A total of seven patients with ICAS-related LVO were included, and the median age of the patients was 76 years. All patients achieved eTICI 3 reperfusion and FPR. The residual stenosis rate ranged from 5 to 10%. None of the patients had re-occlusion post-procedure. The median puncture-to-reperfusion time was 51 min. None of the patients had a symptomatic cerebral hemorrhage, re-occlusion, distal embolism, and dissection. Good clinical outcomes were observed in four patients (4/7, 57.1%), and 1 patient (1/7, 14.3%) died. Conclusion: The BASIS technique is feasible and safe for treating acute ICAS-related LVO.

Integrin α5 Is Regulated by miR-218-5p in Endothelial Progenitor Cells.

BACKGROUND: Endothelial cell injury is a common nidus of renal injury in patients and consistent with the high prevalence of AKI reported during the coronavirus disease 2019 pandemic. This cell type expresses integrin α5 (ITGA5), which is essential to the Tie2 signaling pathway. The microRNA miR-218-5p is upregulated in endothelial progenitor cells (EPCs) after hypoxia, but microRNA regulation of Tie2 in the EPC lineage is unclear. METHODS: We isolated human kidney-derived EPCs (hkEPCs) and surveyed microRNA target transcripts. A preclinical model of ischemic kidney injury was used to evaluate the effect of hkEPCs on capillary repair. We used a genetic knockout model to evaluate the effect of deleting endogenous expression of miR-218 specifically in angioblasts. RESULTS: After ischemic in vitro preconditioning, miR-218-5p was elevated in hkEPCs. We found miR-218-5p bound to ITGA5 mRNA transcript and decreased ITGA5 protein expression. Phosphorylation of 42/44 MAPK decreased by 73.6% in hkEPCs treated with miR-218-5p. Cells supplemented with miR-218-5p downregulated ITGA5 synthesis and decreased 42/44 MAPK phosphorylation. In a CD309-Cre/miR-218-2-LoxP mammalian model (a conditional knockout mouse model designed to delete pre-miR-218-2 exclusively in CD309+ cells), homozygotes at e18.5 contained avascular glomeruli, whereas heterozygote adults showed susceptibility to kidney injury. Isolated EPCs from the mouse kidney contained high amounts of ITGA5 and showed decreased migratory capacity in three-dimensional cell culture. CONCLUSIONS: These results demonstrate the critical regulatory role of miR-218-5p in kidney EPC migration, a finding that may inform efforts to treat microvascular kidney injury via therapeutic cell delivery.

Association of baseline core volume and early midline shift in acute stroke patients with a large ischaemic core.

Background: Midline shift (MLS) is troublesome problem that may occur in patients with a large infarct core (LIC) and may be related to the baseline infarct core volume. The purpose of this study was to explore the relationship between baseline infarct core volume and early MLS presence. Materials and methods: Patients with acute intracranial large artery occlusion and a pretreatment relative cerebral blood flow (rCBF) <30% volume ≥50 ml on CT perfusion (CTP) were included, clinical outcomes following endovascular treatment (EVT) were retrospectively analyzed. The primary endpoint was MLS within 48 h (early MLS presence). The association between baseline ICV and early MLS presence was evaluated with multivariable regression. Results: Ultimately, 95 patients were included, and 29.5% (28/95) of the patients had early MLS. The number of patients with a baseline rCBF < 15% volume (median [interquartile range], 46 [32-60] vs. 29 [19-40]; P < 0.001) was significantly larger in the early severe MLS presence group. A baseline rCBF < 15% volume showed significantly better predictive accuracy for early MLS presence than an rCBF < 30% volume (area under the curve, 0.74 vs. 0.64, P = 0.0023). In addition, an rCBF < 15% volume ≥40 ml (odds ratio, 4.34 [95% CI, 1.571-11.996]) was associated with early MLS presence after adjustment for sex, age, baseline National Institutes of Health Stroke Scale score, onset-to-recanalization time. Conclusion: In patients with an acute LIC following EVT, a pretreatment infarct core volume > 40 ml based on an rCBF < 15% showed good predictive value for early MLS occurrence.

ATP-binding cassette protein ABCF1 couples transcription and genome surveillance in embryonic stem cells through low-complexity domain.

OCT4 and SOX2 confer pluripotency by recruiting coactivators to activate stem cell­specific transcription. However, the composition of coactivator complexes and their roles in maintaining stem cell fidelity remain unclear. Here, we report the ATP-binding cassette subfamily F member 1 (ABCF1) as a coactivator for OCT4/SOX2 critical for stem cell self-renewal. The intrinsically disordered low-complexity domain (LCD) of ABCF1 contributes to phase separation in vitro and transcriptional activation of pluripotency genes by mediating multivalent interactions with SOX2 and co-dependent coactivators XPC and DKC1. These LCD-driven transcription factor­coactivator interactions critical for pluripotency gene expression are disrupted by DNA damage, likely due to LCD-dependent binding of ABCF1 to damage-generated intracellular DNA fragments instead of SOX2. This study identifies a transcriptional coactivator that uses its LCD to form selective multivalent interactions to regulate stem cell self-renewal and exit from pluripotency when genome integrity is compromised.

Initial Clinical Experience of Repeat Thrombectomy with a Retrieval Stent (RTRS) with Continuous Proximal Flow Arrest by Balloon Guide Catheter for Acute Intracranial Carotid Occlusion.

BACKGROUND: Balloon guide catheters (BGCs) have good performance in terms of radiological outcomes in acute ischemic thrombectomy. It is not uncommon for BGCs to be blocked by thrombi, especially in cases with acute intracranial internal carotid artery (ICA) occlusion. Our initial experience using repeat thrombectomy with a retrieval stent (RTRS) with continuous proximal flow arrest by BGC for acute intracranial ICA occlusion is presented. METHODS: In patients with acute intracranial ICA occlusion treated with RTRS, clinical data, including the National Institutes of Health Stroke Scale (NIHSS) score at admission and modified Rankin Scale (mRS) score at 90 days, and procedural data, including the Extended treatment in Cerebral Infarction (eTICI) score, procedural time, and complications, were analyzed. RESULTS: Thirty-two consecutive patients (12 men (37.5%); mean age: 73 years) were treated with RTRS using a BGC. The median NIHSS score was 19. The median puncture-to-reperfusion time was 46 minutes (range: 22-142 minutes). All patients were successfully revascularized; eTICI 2c or better recanalization was achieved in 30 (93.8%) patients. No procedure-related complications or symptomatic intracranial hemorrhage occurred. Two cases (6.3%) had distal emboli, but none had emboli to the anterior cerebral artery. Fourteen patients (43.8%) achieved a good outcome with an mRS score of 0-2 at 90 days, and 8 patients (25.0%) died. CONCLUSIONS: In patients with intracranial ICA occlusion, RTRS with proximal flow arrest by BGC is effective and safe, achieving good clinical and angiographic outcomes. This method may reduce the incidence of distal emboli in thrombectomy with stent retrievers.

Phosphorylation of ACTN4 Leads to Podocyte Vulnerability and Proteinuric Glomerulosclerosis.

BACKGROUND: Genetic mutations in α-actinin-4 (ACTN4)-an important actin crosslinking cytoskeletal protein that provides structural support for kidney podocytes-have been linked to proteinuric glomerulosclerosis in humans. However, the effect of post-translational modifications of ACTN4 on podocyte integrity and kidney function is not known. METHODS: Using mass spectrometry, we found that ACTN4 is phosphorylated at serine (S) 159 in human podocytes. We used phosphomimetic and nonphosphorylatable ACTN4 to comprehensively study the effects of this phosphorylation in vitro and in vivo. We conducted x-ray crystallography, F-actin binding and bundling assays, and immunofluorescence staining to evaluate F-actin alignment. Microfluidic organ-on-a-chip technology was used to assess for detachment of podocytes simultaneously exposed to fluid flow and cyclic strain. We then used CRISPR/Cas9 to generate mouse models and assessed for renal injury by measuring albuminuria and examining kidney histology. We also performed targeted mass spectrometry to determine whether high extracellular glucose or TGF-ß levels increase phosphorylation of ACTN4. RESULTS: Compared with the wild type ACTN4, phosphomimetic ACTN4 demonstrated increased binding and bundling activity with F-actin in vitro. Phosphomimetic Actn4 mouse podocytes exhibited more spatially correlated F-actin alignment and a higher rate of detachment under mechanical stress. Phosphomimetic Actn4 mice developed proteinuria and glomerulosclerosis after subtotal nephrectomy. Moreover, we found that exposure to high extracellular glucose or TGF-ß stimulates phosphorylation of ACTN4 at S159 in podocytes. CONCLUSIONS: These findings suggest that increased phosphorylation of ACTN4 at S159 leads to biochemical, cellular, and renal pathology that is similar to pathology resulting from human disease-causing mutations in ACTN4. ACTN4 may mediate podocyte injury as a consequence of both genetic mutations and signaling events that modulate phosphorylation.

Kymolyzer, a Semi-Autonomous Kymography Tool to Analyze Intracellular Motility.

The movement of intracellular cargo, such as transcripts, proteins, and organelles, is fundamental to cellular function. Neurons, due to their long axons and dendrites, are particularly dependent on proper intracellular trafficking and vulnerable to defects in the movement of intracellular cargo that are noted in neurodegenerative and neurodevelopmental disorders. Accurate quantification of intracellular transport is therefore needed for studying the mechanisms of cargo trafficking, the influence of mutations, and the effects of potentially therapeutic pharmaceuticals. In this article, we introduce an algorithm called "Kymolyzer." The algorithm can quantify intracellular trafficking along a defined path, such as that formed by the aligned microtubules of axons and dendrites. Kymolyzer works as a semi-autonomous kymography software application. It constructs and analyzes kymographs to measure the movement and distribution of fluorescently tagged objects along a user-defined path. The algorithm can be used under a wide variety of experimental conditions and can extract a diverse array of motility parameters describing intracellular movement, including time spent in motion, percentage of objects in motion, percentage of objects that are stationary, and velocities of motile objects. This article serves as a user manual describing the design of Kymolyzer, providing a stepwise protocol for its use and illustrating its functions with common examples. © 2020 Wiley Periodicals LLC Basic Protocol: Kymolyzer, a semi-autonomous kymography tool to analyze intracellular motility.

Stent-unsheathed effect predicts acute distal middle cerebral artery atherosclerotic disease-related occlusion.

BACKGROUND: The differentiation of intracranial atherosclerosis (ICAS) and embolism is important. OBJECTIVE: In cases of ICAS, we observe a phenomenon that we call the "post-stent-deployment effect"; that is, all major branches are clearly visible beyond the occlusion segment when the stent is deployed at the site of occlusion. Our objective is to evaluates whether this post-stent-deployment effect can be used to differentiate ICAS from embolism in the distal M1 segment occlusion. METHODS: We conduct a retrospective study which reviewed consecutive patients with acute distal M1 segment and in whom recanalization was achieved by endovascular treatment. The post-stent-deployment effect was assessed in these patients. The sensitivity, specificity, positive predictive values (PPV), and accuracy of the post-stent-deployment effect for prediction of ICAS were assessed. RESULTS: From January 2015 to July 2018, a total of 80 patients were evaluated. The post-stent-deployment effect was more frequently observed in patients with ICAS than in those with embolism (100% vs 15.0%, P < .001). For identifying ICAS in distal M1 segment, the sensitivity, specificity, PPV, and accuracy of the post-stent-deployment effect were 100%, 85.0%, 69.0%, and 88.7%, respectively. CONCLUSION: Our study finds that the sensitivity and accuracy of the post-stent-deployment effect in predicting distal M1 segment ICAS occlusion in patients with acute symptoms was high, and it may be useful in identifying ICAS lesion.

PrP is a central player in toxicity mediated by soluble aggregates of neurodegeneration-causing proteins.

Neurodegenerative diseases are an enormous public health problem, affecting tens of millions of people worldwide. Nearly all of these diseases are characterized by oligomerization and fibrillization of neuronal proteins, and there is great interest in therapeutic targeting of these aggregates. Here, we show that soluble aggregates of α-synuclein and tau bind to plate-immobilized PrP in vitro and on mouse cortical neurons, and that this binding requires at least one of the same N-terminal sites at which soluble Aß aggregates bind. Moreover, soluble aggregates of tau, α-synuclein and Aß cause both functional (impairment of LTP) and structural (neuritic dystrophy) compromise and these deficits are absent when PrP is ablated, knocked-down, or when neurons are pre-treated with anti-PrP blocking antibodies. Using an all-human experimental paradigm involving: (1) isogenic iPSC-derived neurons expressing or lacking PRNP, and (2) aqueous extracts from brains of individuals who died with Alzheimer's disease, dementia with Lewy bodies, and Pick's disease, we demonstrate that Aß, α-synuclein and tau are toxic to neurons in a manner that requires PrPC. These results indicate that PrP is likely to play an important role in a variety of late-life neurodegenerative diseases and that therapeutic targeting of PrP, rather than individual disease proteins, may have more benefit for conditions which involve the aggregation of more than one protein.

Clinical significance of common-stem lenticulostriate arteries in patients with internal watershed infarction.

BACKGROUND: A common-stem origin of lenticulostriate arteries (CS-LSAs) is an anatomical variation that supplies a moderate to large section of the basal ganglia. We hypothesized that CS-LSAs with a patent orifice are located at distal positions of the acute-occluded middle cerebral artery (MCA) and that the blood flow of CS-LSAs is supplied by pail arterial anastomoses and results in hypoperfusion of CS-LSAs, similar to a deep watershed (DWS) infarction. OBJECTIVE: Our study evaluated the possibility of CS-LSAs in patients with DWS infarction and MCA occlusion and also assessed the safety of endovascular therapy (ET) in these patients. METHODS: A cohort of consecutive patients with DWS infarction and MCA occlusion and in whom full recanalization via ET was achieved were identified. Patients were divided into two groups based on the presence of CS-LSAs observed during ET. In addition, radiological and clinical data were retrospectively analyzed. RESULTS: Thirty-three patients were included, and CS-LSAs were observed in 48.5% (16/33) of patients. The possibility (72.2%, 13/18) of CS-LSAs was high in patients with DWS infarction companied with basal ganglia infarction. A good clinical outcome was similar in patients with CS-LSAs and basal ganglia infarction and in patients without CS-LSAs and basal ganglia infarction (69.2% vs. 81.8%, P = 0.649). CONCLUSIONS: The possibility of CS-LSAs was 48.5% in patients with DWS infarction and MCA occlusion, and the revascularization procedure was safe and feasible in these patients despite the moderate-to-large basal ganglia infarction.

Cytomegalovirus promotes murine glioblastoma growth via pericyte recruitment and angiogenesis.

Cytomegalovirus (CMV) has been implicated in glioblastoma (GBM); however, a mechanistic connection in vivo has not been established. The purpose of this study is to characterize the effects of murine CMV (MCMV) on GBM growth in murine models. Syngeneic GBM models were established in mice perinatally infected with MCMV. We found that tumor growth was markedly enhanced in MCMV+ mice, with a significant reduction in overall survival compared with that of controls (P < 0.001). We observed increased angiogenesis and tumor blood flow in MCMV+ mice. MCMV reactivation was observed in intratumoral perivascular pericytes and tumor cells in mouse and human GBM specimens, and pericyte coverage of tumor vasculature was strikingly augmented in MCMV+ mice. We identified PDGF-D as a CMV-induced factor essential for pericyte recruitment, angiogenesis, and tumor growth. The antiviral drug cidofovir improved survival in MCMV+ mice, inhibiting MCMV reactivation, PDGF-D expression, pericyte recruitment, and tumor angiogenesis. These data show that MCMV potentiates GBM growth in vivo by increased pericyte recruitment and angiogenesis due to alterations in the secretome of CMV-infected cells. Our model provides evidence for a role of CMV in GBM growth and supports the application of antiviral approaches for GBM therapy.

Safety of Endovascular Therapy in Progressive Ischemic Stroke and Anterior Circulation Large Artery Occlusion.

BACKGROUND AND OBJECTIVE: The prognosis of progressive ischemic stroke (PIS) caused by large proximal artery occlusion with hemodynamic was poor. Our study aimed to investigate the safety of endovascular therapy (ET) for patients with PIS who were selected based on ischemic penumbra detected on brain imaging. METHODS: A cohort of consecutive patients with PIS, who were treated with ET, were identified. Patients were selected for ET based on the presence of ischemic penumbra using magnetic resonance imaging. Clinical outcome includes 90-day modified Rankin scale, mortality, and symptomatic intracerebral hemorrhage (sICH) rate. Multivariate analysis was performed to compare treatment time of ≤6 hours (early) with >6 hours (late) after stroke. RESULTS: One hundred forty-eight patients were treated (100 early and 48 late). Compared with the early group, more successful recanalization rate in the late group (100% vs. 89%, P = 0.017), lower mortality (2.1% vs. 12%, P = 0.046), better clinical outcome (modified Rankin scale score ≤2, 81.3% vs. 65%, P = 0.046), and sICH rate was similar between the 2 groups (7.0% vs. 9.5%, P = 1.00). Only pretreatment National Institutes of Health Stroke Scale score (odds ratio [OR] = 0.836, P = 0.025), successful recanalization (OR = 7.077, P = 0.038), collateral status (OR = 3.121, P = 0.016), and sICH (OR = 0.053, P = 0.013) were predictors of a good prognosis. CONCLUSIONS: In appropriately selected patients with PIS, ET can be performed safely. Furthermore, randomized clinical trials are needed to assess its effectiveness.

Endovascular Therapy Strategy for Acute Embolic Tandem Occlusion: The Pass-Thrombectomy-Protective Thrombectomy (Double PT) Technique.

OBJECTIVE: Embolic occlusions of the common carotid artery (CCA)/internal carotid artery (ICA) and intracranial artery occlusions in acute ischemic stroke are associated with high morbidity and can benefit from endovascular therapy. However, the optimal endovascular strategy for these conditions is unclear. This study aimed to evaluate the feasibility of the pass-thrombectomy-protective thrombectomy (double PT) technique and the clinical outcome of treated patients. METHODS: We collected data on embolic occlusion of the CCA/ICA and intracranial artery occlusion in our prospective stroke registry database between January 2015 and February 2017. Clinical and angiographic data were retrospectively analyzed. Clinical outcome was evaluated at 3 months (modified Rankin scale [mRS] score), and an mRS score of 2 or lower was defined as a good clinical outcome. RESULTS: A total of 7 patients with tandem occlusion were included, with a mean age of 66 years. The median admission National Institutes of Health Stroke Scale score was 20, and 6 of 7 patients (85.7%) underwent successful recanalization. The median reperfusion time of the affected intracranial artery was 61 minutes. The rate of good clinical outcome was 42.9% (3/7), the mortality rate was 14.3% (1/7), and the embolic event rate was 14.3% (1/7) when the proximal clot was retrieved. CONCLUSIONS: The double PT technique is feasible and safe in treating initial embolic tandem occlusion of the CCA/ICA.

Adjuvant intra-arterial rt-PA injection at the initially deployed solitaire stent enhances the efficacy of mechanical thrombectomy in acute ischemic stroke.

BACKGROUND: Both intra-arterial recombinant tissue plasminogen activator (rt-PA) and stent retrieval are effective for treating acute ischemic stroke. The goal of this study was to evaluate the effectiveness of stent retrieval combined with intra-arterial rt-PA administration via micro-catheter (called the complex technique) in acute ischemic stroke. MATERIAL AND METHODS: A retrospective analysis was performed of 93 consecutive patients treated between 2015 and 2017 for occlusions of the intracranial large artery using the complex technique (n=37) or stent retrieval alone (n=56) in our stroke center. Data on procedure duration, number of passes, and angiographic findings were collected. Successful recanalization was defined as the accomplishment of grade 3 or 2b modified Treatment in Cerebral Ischemia recanalization in 1 or 2 passes. RESULTS: Compared to the stent retrieval group, complex technique group had a higher successful revascularization rate with 1 or 2 passes with the stent retriever (81.1% versus 51.8%, P=0.004), a shorter procedure time (59±34min versus 94±56min, P<0.001), fewer passes of the stent retriever (1.8±1.1 versus 2.5±1.4, P=0.012), a better prognosis (70.3% versus 48.2%, P=0.035), a lower embolic complication rate (18.9% versus 39.3%, P=0.038), similar mortality (13.5% versus 21.4%, P=0.334) and similar intracranial hemorrhage symptoms (2.7% versus 12.5%, P=0.204). Intra-arterial rt-PA administration was an independent negative predictor of procedure time (OR=-0.292, P=0.003). CONCLUSION: Mechanical thrombectomy utilizing stent retrieval combined with intra-arterial rt-PA administration in the anterior circulation of acute ischemic stroke patients improved the angiographic results and shortened the procedure duration without increasing adverse events.

Another Endovascular Therapy Strategy for Acute Tandem Occlusion: Protect-Expand-Aspiration-Revascularization-Stent (PEARS) Technique.

OBJECTIVE: Initial stenotic occlusion of the internal carotid artery with intracranial artery occlusion in acute ischemic stroke is associated with high morbidity and can benefit from endovascular therapy. However, the optimal endovascular strategy is unclear. This study aimed to evaluate the feasibility of the "half" anterograde approach and clinical outcome of treated patients. Revascularization validity of the 2 "half" anterograde approach with (Protect-Expand-Aspiration-Revascularization-Stent [PEARS] technique) or without (plain technique) using an embolic prevention device and aspiration was also compared. METHODS: Data on initial stenotic occlusion of the internal carotid artery with intracranial artery occlusion in our prospective stroke registry database between January 2015 and February 2017 were collected. Clinical and angiographic data were retrospectively analyzed. Clinical outcome was evaluated at 3 months, defined as a modified Rankin scale ≤2 as a good clinical outcome. RESULTS: Overall, 26 patients with tandem occlusion were included; 96.3% of patients had successful recanalization. The rate of a good clinical outcome was 61.8%, symptomatic parenchymal hemorrhage was 7.7%, and mortality was 15.4%. The PEARS technique took less time (56 ± 14 vs. 97 ± 31 minutes; P = 0.002) and had less embolic events (0 vs. 30.8%; P = 0.012) compared with the plain technique. Use of the PEARS technique was an independent predictor for shortening revascularization time (ß = -0.651, P = 0.001). CONCLUSIONS: The half anterograde approach technique is feasible and safe for treating tandem occlusion. Furthermore, the PEARS technique is associated with a shorter reperfusion time and less embolic events than the plain technique, and should be recommended in tandem occlusion.

Polycystin-1 and Gα12 regulate the cleavage of E-cadherin in kidney epithelial cells.

Interaction of polycystin-1 (PC1) and Gα12 is important for development of kidney cysts in autosomal dominant polycystic kidney disease (ADPKD). The integrity of cell polarity and cell-cell adhesions (mainly E-cadherin-mediated adherens junction) is altered in the renal epithelial cells of ADPKD. However, the key signaling pathway for this alteration is not fully understood. Madin-Darby canine kidney (MDCK) cells maintain the normal integrity of epithelial cell polarity and adherens junctions. Here, we found that deletion of Pkd1 increased activation of Gα12, which then promoted the cystogenesis of MDCK cells. The morphology of these cells was altered after the activation of Gα12. By using liquid chromatography-mass spectrometry, we found several proteins that could be related this change in the extracellular milieu. E-cadherin was one of the most abundant peptides after active Gα12 was induced. Gα12 activation or Pkd1 deletion increased the shedding of E-cadherin, which was mediated via increased ADAM10 activity. The increased shedding of E-cadherin was blocked by knockdown of ADAM10 or specific ADAM10 inhibitor GI254023X. Pkd1 deletion or Gα12 activation also changed the distribution of E-cadherin in kidney epithelial cells and caused ß-catenin to shift from cell membrane to nucleus. Finally, ADAM10 inhibitor, GI254023X, blocked the cystogenesis induced by PC1 knockdown or Gα12 activation in renal epithelial cells. Our results demonstrate that the E-cadherin/ß-catenin signaling pathway is regulated by PC1 and Gα12 via ADAM10. Specific inhibition of this pathway, especially ADAM10 activity, could be a novel therapeutic regimen for ADPKD.

Mice with hepatocyte-specific deficiency of type 3 deiodinase have intact liver regeneration and accelerated recovery from nonthyroidal illness after toxin-induced hepatonecrosis.

Type 3 deiodinase (D3), the physiologic inactivator of thyroid hormones, is induced during tissue injury and regeneration. This has led to the hypotheses that D3 impacts injury tolerance by reducing local T3 signaling and contributes to the fall in serum triiodothyronine (T3) observed in up to 75% of sick patients (termed the low T3 syndrome). Here we show that a novel mutant mouse with hepatocyte-specific D3 deficiency has normal local responses to toxin-induced hepatonecrosis, including normal degrees of tissue necrosis and intact regeneration, but accelerated systemic recovery from illness-induced hypothyroxinemia and hypotriiodothyroninemia, demonstrating that peripheral D3 expression is a key modulator of the low T3 syndrome.