The m6A reader YTHDC2 is essential for escape from KSHV SOX-induced RNA decay.

The role of N6-methyladenosine (m6A) modifications has increasingly been associated with a diverse set of roles in modulating viruses and influencing the outcomes of viral infection. Here, we report that the landscape of m6A deposition is drastically shifted during Kaposi's sarcoma-associated herpesvirus (KSHV) lytic infection for both viral and host transcripts. In line with previous reports, we also saw an overall decrease in host methylation in favor of viral messenger RNA (mRNA), along with 5' hypomethylation and 3' hypermethylation. During KSHV lytic infection, a major shift in overall mRNA abundance is driven by the viral endoribonuclease SOX, which induces the decay of greater than 70% of transcripts. Here, we reveal that interlukin-6 (IL-6) mRNA, a well-characterized, SOX-resistant transcript, is m6A modified during lytic infection. Furthermore, we show that this modification falls within the IL-6 SOX resistance element, an RNA element in the IL-6 3' untranslated region (UTR) that was previously shown to be sufficient for protection from SOX cleavage. We show that the presence of this m6A modification is essential to confer SOX resistance to the IL-6 mRNA. We next show that this modification recruits the m6A reader YTHDC2 and found that YTHDC2 is necessary for the escape of the IL-6 transcript. These results shed light on how the host cell has evolved to use RNA modifications to circumvent viral manipulation of RNA fate during KSHV infection.

Fated for decay: RNA elements targeted by viral endonucleases.

For over a decade, studies of messenger RNA regulation have revealed an unprecedented level of connectivity between the RNA pool and global gene expression. These connections are underpinned by a vast array of RNA elements that coordinate RNA-protein and RNA-RNA interactions, each directing mRNA fate from transcription to translation. Consequently, viruses have evolved an arsenal of strategies to target these RNA features and ultimately take control of the pathways they influence, and these strategies contribute to the global shutdown of the host gene expression machinery known as "Host Shutoff". This takeover of the host cell is mechanistically orchestrated by a number of non-homologous virally encoded endoribonucleases. Recent large-scale screens estimate that over 70 % of the host transcriptome is decimated by the expression of these viral nucleases. While this takeover strategy seems extraordinarily well conserved, each viral endonuclease has evolved to target distinct mRNA elements. Herein, we will explore each of these RNA structures/sequence features that render messenger RNA susceptible or resistant to viral endonuclease cleavage. By further understanding these targeting and escape mechanisms we will continue to unravel untold depths of cellular RNA regulation that further underscores the integral relationship between RNA fate and the fate of the cell.

Shiftless Restricts Viral Gene Expression and Influences RNA Granule Formation during Kaposi's Sarcoma-Associated Herpesvirus Lytic Replication.

Herpesviral infection reflects thousands of years of coevolution and the constant struggle between virus and host for control of cellular gene expression. During Kaposi's sarcoma-associated herpesvirus (KSHV) lytic replication, the virus rapidly seizes control of host gene expression machinery by triggering a massive RNA decay event via a virally encoded endoribonuclease, SOX. This virus takeover strategy decimates close to 80% of cellular transcripts, reallocating host resources toward viral replication. The host cell, however, is not entirely passive in this assault on RNA stability. A small pool of host transcripts that actively evade SOX cleavage has been identified over the years. One such "escapee," C19ORF66 (herein referred to as Shiftless [SHFL]), encodes a potent antiviral protein capable of restricting the replication of multiple DNA and RNA viruses and retroviruses, including KSHV. Here, we show that SHFL restricts KSHV replication by targeting the expression of critical viral early genes, including the master transactivator protein, KSHV ORF50, and thus subsequently the entire lytic gene cascade. Consistent with previous reports, we found that the SHFL interactome throughout KSHV infection is dominated by RNA-binding proteins that influence both translation and protein stability, including the viral protein ORF57, a crucial regulator of viral RNA fate. We next show that SHFL affects cytoplasmic RNA granule formation, triggering the disassembly of processing bodies. Taken together, our findings provide insights into the complex relationship between RNA stability, RNA granule formation, and the antiviral response to KSHV infection. IMPORTANCE In the past 5 years, SHFL has emerged as a novel and integral piece of the innate immune response to viral infection. SHFL has been reported to restrict the replication of multiple viruses, including several flaviviruses and the retrovirus HIV-1. However, to date, the mechanism(s) by which SHFL restricts DNA virus infection remains largely unknown. We have previously shown that following its escape from KSHV-induced RNA decay, SHFL acts as a potent antiviral factor, restricting nearly every stage of KSHV lytic replication. In this study, we set out to determine the mechanism by which SHFL restricts KSHV infection. We demonstrate that SHFL impacts all classes of KSHV genes and found that SHFL restricts the expression of several key early genes, including KSHV ORF50 and ORF57. We then mapped the interactome of SHFL during KSHV infection and found several host and viral RNA-binding proteins that all play crucial roles in regulating RNA stability and translation. Lastly, we found that SHFL expression influences RNA granule formation both outside and within the context of KSHV infection, highlighting its broader impact on global gene expression. Collectively, our findings highlight a novel relationship between a critical piece of the antiviral response to KSHV infection and the regulation of RNA-protein dynamics.

Lipoprotein(a) is associated with large artery atherosclerosis stroke aetiology and stroke recurrence among patients below the age of 60 years: results from the BIOSIGNAL study.

AIMS: Lipoprotein(a) [Lp(a)] is a recognized causal risk factor for atherosclerotic cardiovascular disease but its role for acute ischaemic stroke (AIS) is controversial. In this study, we evaluated the association of Lp(a) with large artery atherosclerosis (LAA) stroke and risk of recurrent cerebrovascular events in AIS patients. METHODS AND RESULTS: For this analysis of the prospective, observational, multicentre BIOSIGNAL cohort study we measured Lp(a) levels in plasma samples of 1733 primarily Caucasian (98.6%) AIS patients, collected within 24 h after symptom onset. Primary outcomes were LAA stroke aetiology and recurrent cerebrovascular events (ischaemic stroke or transient ischaemic attack) within 1 year. We showed that Lp(a) levels are independently associated with LAA stroke aetiology [adjusted odds ratio 1.48, 95% confidence interval (CI) 1.14-1.90, per unit log10Lp(a) increase] and identified age as a potent effect modifier (Pinteraction =0.031) of this association. The adjusted odds ratio for LAA stroke in patients aged <60 years was 3.64 (95% CI 1.76-7.52) per unit log10Lp(a) increase and 4.04 (95% CI 1.73-9.43) using the established cut-off ≥100 nmol/l. For 152 recurrent cerebrovascular events, we did not find a significant association in the whole cohort. However, Lp(a) levels ≥100 nmol/l were associated with an increased risk for recurrent events among patients who were either <60 years [adjusted hazard ratio (HR) 2.40, 95% CI 1.05-5.47], had evident LAA stroke aetiology (adjusted HR 2.18, 95% CI 1.08-4.40), or had no known atrial fibrillation (adjusted HR 1.60, 95% CI 1.03-2.48). CONCLUSION: Elevated Lp(a) was independently associated with LAA stroke aetiology and risk of recurrent cerebrovascular events among primarily Caucasian individuals aged <60 years or with evident arteriosclerotic disease.

Arterial collateral anatomy predicts the risk for intra-operative changes in somatosensory evoked potentials in patients undergoing carotid endarterectomy: a prospective cohort study.

BACKGROUND: During carotid endarterectomy (CEA), significant amplitude decrement of somatosensory evoked potentials (SEPs) is associated with post-operative neurological deficits. OBJECTIVE: To investigate the association between an incomplete circle of Willis and/or contralateral ICA occlusion and subsequent changes in intra-operatively monitored SEPs. METHODS: We performed a retrospective analysis of a single center, prospective cohort of consecutive patients undergoing CEA over a 42-month period after reviewing the collateral arterial anatomy on pre-operative radiological imaging. The primary endpoint was an intra-operative decline in SEPs > 50% compared to the baseline value during arterial cross-clamping. Univariate and multivariate logistic regression analyses were performed to investigate a potential association between contralateral ICA occlusion, incomplete circle of Willis, and subsequent alteration in SEPs. RESULTS: A total of 140 consecutive patients were included, of which 116 patients (82.9%) had symptomatic carotid stenosis of at least 50% according to the classification used in the North American Carotid Surgery Trial (NASCET) (Stroke 22:711-720, 1991). Six patients (4.3%) showed contralateral ICA occlusion, 22 patients (16%) a missing/hypoplastic anterior communicating artery (Acom) or A1 segment, and 79 patients (56%) a missing ipsilateral posterior communicating artery (Pcom) or P1 segment. ICA occlusion and missing segments of the anterior circulation (missing A1 and/or missing Acom) were associated with the primary endpoint (p = 0.003 and p = 0.022, respectively). CONCLUSION: Contralateral ICA occlusion and missing anterior collaterals of the circle of Willis increase the risk of intra-operative SEP changes during CEA. Pre-operative assessment of collateral arterial anatomy might help identifying patients with an increased intra-operative risk.

[Atherosclerosis of the intracranial arteries and of the extracranial carotid artery.] / Atherosklerose der intrakraniellen Arterien und der extrakraniellen Karotis.

Atherosclerosis of the intracranial arteries and of the extracranial carotid artery. Abstract. Intracranial atherosclerotic stenoses are the most common cause of ischemic stroke worldwide. Nowadays, three therapeutic approaches are available for consideration for patients with intracranial atherosclerotic stenoses: A conservative therapy (best medical treatment, management of vascular risk factors and healthy lifestyle), endovascular and surgical therapy. Conservative approach has been recommended for patients with asymptomatic intracranial atherosclerotic stenoses, as well as for those with symptomatic stenoses. Endovascular therapy should be considered as a treatment option for carefully selected patients with recurrent ischemic strokes attributed to the stenotic artery while receiving best medical therapy. Surgical revascularisation is rarely favored in patients with intracranial stenoses. In patients with extracranial atherosclerotic stenoses, carotid endarterectomy (CEA) has been associated with a lower risk of death and recurrent stroke when compared to carotid angioplasty and stenting (CAS). Especially in elderly patients over 70 years of age CEA is preferred over CAS due to the twofold increased 30-day risk of recurrent stroke or death in patients treated with CAS. Results from contemporary studies using modern techniques and devices are expected. It remains unclear whether patients with asymptomatic extracranial atherosclerotic stenoses receiving best medical treatment would benefit of invasive procedures such as CEA or CAS.

C19ORF66 Broadly Escapes Virus-Induced Endonuclease Cleavage and Restricts Kaposi's Sarcoma-Associated Herpesvirus.

One striking characteristic of certain herpesviruses is their ability to induce rapid and widespread RNA decay in order to gain access to host resources. This phenotype is induced by viral endoribonucleases, including SOX in Kaposi's sarcoma-associated herpesvirus (KSHV), muSOX in murine gammaherpesvirus 68 (MHV68), BGLF5 in Epstein-Barr virus (EBV), and vhs in herpes simplex virus 1 (HSV-1). Here, we performed comparative transcriptome sequencing (RNA-seq) upon expression of these herpesviral endonucleases in order to characterize their effect on the host transcriptome. Consistent with previous reports, we found that approximately two-thirds of transcripts were downregulated in cells expressing any of these viral endonucleases. Among the transcripts spared from degradation, we uncovered a cluster of transcripts that systematically escaped degradation from all tested endonucleases. Among these escapees, we identified C19ORF66 and reveal that this transcript is protected from degradation by its 3' untranslated region (UTR). We then show that C19ORF66 is a potent KSHV restriction factor by impeding early viral gene expression, suggesting that its ability to escape viral cleavage may be an important component of the host response to viral infection. Collectively, our comparative approach is a powerful tool to pinpoint key regulators of the viral-host interplay and led us to uncover a novel KSHV regulator.IMPORTANCE Viruses are master regulators of the host gene expression machinery. This is crucial to promote viral infection and to dampen host immune responses. Many viruses, including herpesviruses, express RNases that reduce host gene expression through widespread mRNA decay. However, it emerged that some mRNAs escape this fate, although it has been difficult to determine whether these escaping transcripts benefit viral infection or instead participate in an antiviral mechanism. To tackle this question, we compared the effect of the herpesviral RNases on the human transcriptome and identified a cluster of transcripts consistently escaping degradation from all tested endonucleases. Among the protected mRNAs, we identified the transcript C19ORF66 and showed that it restricts Kaposi's sarcoma-associated herpesvirus (KSHV) infection. Collectively, these results provide a framework to explore how the control of RNA fate in the context of viral-induced widespread mRNA degradation may influence the outcome of viral infection.

Carotid artery stenting versus endarterectomy for treatment of carotid artery stenosis.

BACKGROUND: Carotid artery stenting is an alternative to carotid endarterectomy for the treatment of atherosclerotic carotid artery stenosis. This review updates a previous version first published in 1997 and subsequently updated in 2004, 2007, and 2012. OBJECTIVES: To assess the benefits and risks of stenting compared with endarterectomy in people with symptomatic or asymptomatic carotid stenosis. SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (last searched August 2018) and the following databases: CENTRAL, MEDLINE, Embase, and Science Citation Index to August 2018. We also searched ongoing trials registers (August 2018) and reference lists, and contacted researchers in the field. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing stenting with endarterectomy for symptomatic or asymptomatic atherosclerotic carotid stenosis. In addition, we included RCTs comparing carotid artery stenting with medical therapy alone. DATA COLLECTION AND ANALYSIS: One review author selected trials for inclusion, assessed trial quality and risk of bias, and extracted data. A second review author independently validated trial selection and a third review author independently validated data extraction. We calculated treatment effects as odds ratios (OR) and 95% confidence intervals (CI), with endarterectomy as the reference group. We quantified heterogeneity using the I² statistic and used GRADE to assess the overall certainty of evidence. MAIN RESULTS: We included 22 trials involving 9753 participants. In participants with symptomatic carotid stenosis, compared with endarterectomy stenting was associated with a higher risk of periprocedural death or stroke (the primary safety outcome; OR 1.70, 95% CI 1.31 to 2.19; P < 0.0001, I² = 5%; 10 trials, 5396 participants; high-certainty evidence); and periprocedural death, stroke, or myocardial infarction (OR 1.43, 95% CI 1.14 to 1.80; P = 0.002, I² = 0%; 6 trials, 4861 participants; high-certainty evidence). The OR for the primary safety outcome was 1.11 (95% CI 0.74 to 1.64) in participants under 70 years old and 2.23 (95% CI 1.61 to 3.08) in participants 70 years old or more (interaction P = 0.007). There was a non-significant increase in periprocedural death or major or disabling stroke with stenting (OR 1.36, 95% CI 0.97 to 1.91; P = 0.08, I² = 0%; 7 trials, 4983 participants; high-certainty evidence). Compared with endarterectomy, stenting was associated with lower risks of myocardial infarction (OR 0.47, 95% CI 0.24 to 0.94; P = 0.03, I² = 0%), cranial nerve palsy (OR 0.09, 95% CI 0.06 to 0.16; P < 0.00001, I² = 0%), and access site haematoma (OR 0.32, 95% CI 0.15 to 0.68; P = 0.003, I² = 27%). The combination of periprocedural death or stroke or ipsilateral stroke during follow-up (the primary combined safety and efficacy outcome) favoured endarterectomy (OR 1.51, 95% CI 1.24 to 1.85; P < 0.0001, I² = 0%; 8 trials, 5080 participants; high-certainty evidence). The rate of ipsilateral stroke after the periprocedural period did not differ between treatments (OR 1.05, 95% CI 0.75 to 1.47; P = 0.77, I² = 0%). In participants with asymptomatic carotid stenosis, there was a non-significant increase in periprocedural death or stroke with stenting compared with endarterectomy (OR 1.72, 95% CI 1.00 to 2.97; P = 0.05, I² = 0%; 7 trials, 3378 participants; moderate-certainty evidence). The risk of periprocedural death or stroke or ipsilateral stroke during follow-up did not differ significantly between treatments (OR 1.27, 95% CI 0.87 to 1.84; P = 0.22, I² = 0%; 6 trials, 3315 participants; moderate-certainty evidence). Moderate or higher carotid artery restenosis (50% or greater) or occlusion during follow-up was more common after stenting (OR 2.00, 95% CI 1.12 to 3.60; P = 0.02, I² = 44%), but the difference in risk of severe restenosis was not significant (70% or greater; OR 1.26, 95% CI 0.79 to 2.00; P = 0.33, I² = 58%; low-certainty evidence). AUTHORS' CONCLUSIONS: Stenting for symptomatic carotid stenosis is associated with a higher risk of periprocedural stroke or death than endarterectomy. This extra risk is mostly attributed to an increase in minor, non-disabling strokes occurring in people older than 70 years. Beyond the periprocedural period, carotid stenting is as effective in preventing recurrent stroke as endarterectomy. However, combining procedural safety and long-term efficacy in preventing recurrent stroke still favours endarterectomy. In people with asymptomatic carotid stenosis, there may be a small increase in the risk of periprocedural stroke or death with stenting compared with endarterectomy. However, CIs of treatment effects were wide and further data from randomised trials in people with asymptomatic stenosis are needed.

Stent Design, Restenosis and Recurrent Stroke After Carotid Artery Stenting in the International Carotid Stenting Study.

Background and Purpose- Open-cell carotid artery stents are associated with a higher peri-procedural stroke risk than closed-cell stents. However, the effect of stent design on long-term durability of carotid artery stenting (CAS) is unknown. We compared the medium- to long-term risk of restenosis and ipsilateral stroke between patients treated with open-cell stents versus closed-cell stents in the ICSS (International Carotid Stenting Study). Methods- Patients with symptomatic carotid stenosis were randomized to CAS or endarterectomy and followed with duplex ultrasound for a median of 4.0 years. We analyzed data from patients with completed CAS procedures, known stent design, and available ultrasound follow-up. The primary outcome, moderate or higher restenosis (≥50%) was defined as a peak systolic velocity of >1.3 m/s on ultrasound or occlusion of the treated internal carotid artery and analyzed with interval-censored models. Results- Eight hundred fifty-five patients were allocated to CAS. Seven hundred fourteen patients with completed CAS and known stent design were included in the current analysis. Of these, 352 were treated with open-cell and 362 with closed-cell stents. Moderate or higher restenosis occurred significantly less frequently in patients treated with open-cell (n=113) than closed-cell stents (n=154; 5-year risks were 35.5% versus 46.0%; unadjusted hazard ratio, 0.68; 95% CI, 0.53-0.88). There was no significant difference in the risk of severe restenosis (≥70%) after open-cell stenting (n=27) versus closed-cell stenting (n=43; 5-year risks, 8.6% versus 12.7%; unadjusted hazard ratio, 0.63; 95% CI, 0.37-1.05). The risk of ipsilateral stroke beyond 30 days after treatment was similar with open-cell and closed-cell stents (hazard ratio, 0.78; 95% CI, 0.35-1.75). Conclusions- Moderate or higher restenosis after CAS occurred less frequently in patients treated with open-cell stents than closed-cell stents. However, both stent designs were equally effective at preventing recurrent stroke during follow-up. Clinical Trial Registration- URL: http://www.isrctn.com/. Unique identifier: ISRCTN25337470.

Nuclease escape elements protect messenger RNA against cleavage by multiple viral endonucleases.

During lytic Kaposi's sarcoma-associated herpesvirus (KSHV) infection, the viral endonu- clease SOX promotes widespread degradation of cytoplasmic messenger RNA (mRNA). However, select mRNAs, including the transcript encoding interleukin-6 (IL-6), escape SOX-induced cleavage. IL-6 escape is mediated through a 3' UTR RNA regulatory element that overrides the SOX targeting mechanism. Here, we reveal that this protective RNA element functions to broadly restrict cleavage by a range of homologous and non-homologous viral endonucleases. However, it does not impede cleavage by cellular endonucleases. The IL-6 protective sequence may be representative of a larger class of nuclease escape elements, as we identified a similar protective element in the GADD45B mRNA. The IL-6 and GADD45B-derived elements display similarities in their sequence, putative structure, and several associated RNA binding proteins. However, the overall composition of their ribonucleoprotein complexes appears distinct, leading to differences in the breadth of nucleases restricted. These findings highlight how RNA elements can selectively control transcript abundance in the background of widespread virus-induced mRNA degradation.

Immediate and Delayed Procedural Stroke or Death in Stenting Versus Endarterectomy for Symptomatic Carotid Stenosis.

Background and Purpose- Stenting for symptomatic carotid stenosis (carotid artery stenting [CAS]) carries a higher risk of procedural stroke or death than carotid endarterectomy (CEA). It is unclear whether this extra risk is present both on the day of procedure and within 1 to 30 days thereafter and whether clinical risk factors differ between these periods. Methods- We analyzed the risk of stroke or death occurring on the day of procedure (immediate procedural events) and within 1 to 30 days thereafter (delayed procedural events) in 4597 individual patients with symptomatic carotid stenosis who underwent CAS (n=2326) or CEA (n=2271) in 4 randomized trials. Results- Compared with CEA, patients treated with CAS were at greater risk for immediate procedural events (110 versus 42; 4.7% versus 1.9%; odds ratio, 2.6; 95% CI, 1.9-3.8) but not for delayed procedural events (59 versus 46; 2.5% versus 2.0%; odds ratio, 1.3; 95% CI, 0.9-1.9; interaction P=0.006). In patients treated with CAS, age increased the risk for both immediate and delayed events while qualifying event severity only increased the risk of delayed events. In patients treated with CEA, we found no risk factors for immediate events while a higher level of disability at baseline and known history of hypertension were associated with delayed procedural events. Conclusions- The increased procedural stroke or death risk associated with CAS compared with CEA was caused by an excess of events occurring on the day of procedure. This finding demonstrates the need to enhance the procedural safety of CAS by technical improvements of the procedure and increased operator skill. Higher age increased the risk for both immediate and delayed procedural events in CAS, mechanisms of which remain to be elucidated. Clinical Trial Registration- URL: https://clinicaltrials.gov . Unique identifier: NCT00190398. URL: http://www.isrctn.com . Unique identifier: ISRCTN57874028. URL: http://www.isrctn.com . Unique identifier: ISRCTN25337470. URL: https://clinicaltrials.gov . Unique identifier: NCT00004732.

Vascular Anatomy Predicts the Risk of Cerebral Ischemia in Patients Randomized to Carotid Stenting Versus Endarterectomy.

BACKGROUND AND PURPOSE: Complex vascular anatomy might increase the risk of procedural stroke during carotid artery stenting (CAS). Randomized controlled trial evidence that vascular anatomy should inform the choice between CAS and carotid endarterectomy (CEA) has been lacking. METHODS: One-hundred eighty-four patients with symptomatic internal carotid artery stenosis who were randomly assigned to CAS or CEA in the ICSS (International Carotid Stenting Study) underwent magnetic resonance (n=126) or computed tomographic angiography (n=58) at baseline and brain magnetic resonance imaging before and after treatment. We investigated the association between aortic arch configuration, angles of supra-aortic arteries, degree, length of stenosis, and plaque ulceration with the presence of ≥1 new ischemic brain lesion on diffusion-weighted magnetic resonance imaging (DWI+) after treatment. RESULTS: Forty-nine of 97 patients in the CAS group (51%) and 14 of 87 in the CEA group (16%) were DWI+ (odds ratio [OR], 6.0; 95% confidence interval [CI], 2.9-12.4; P<0.001). In the CAS group, aortic arch configuration type 2/3 (OR, 2.8; 95% CI, 1.1-7.1; P=0.027) and the degree of the largest internal carotid artery angle (≥60° versus <60°; OR, 4.1; 95% CI, 1.7-10.1; P=0.002) were both associated with DWI+, also after correction for age. No predictors for DWI+ were identified in the CEA group. The DWI+ risk in CAS increased further over CEA if the largest internal carotid artery angle was ≥60° (OR, 11.8; 95% CI, 4.1-34.1) than if it was <60° (OR, 3.4; 95% CI, 1.2-9.8; interaction P=0.035). CONCLUSIONS: Complex configuration of the aortic arch and internal carotid artery tortuosity increase the risk of cerebral ischemia during CAS, but not during CEA. Vascular anatomy should be taken into account when selecting patients for stenting. CLINICAL TRIAL REGISTRATION: URL: http://www.isrctn.com/ISRCTN25337470. Unique identifier: ISRCTN25337470.

A ribonucleoprotein complex protects the interleukin-6 mRNA from degradation by distinct herpesviral endonucleases.

During lytic Kaposi's sarcoma-associated herpesvirus (KSHV) infection, the viral endonuclease SOX promotes widespread degradation of cytoplasmic messenger RNA (mRNA). However, select mRNAs escape SOX-induced cleavage and remain robustly expressed. Prominent among these is interleukin-6 (IL-6), a growth factor important for survival of KSHV infected B cells. IL-6 escape is notable because it contains a sequence within its 3' untranslated region (UTR) that can confer protection when transferred to a SOX-targeted mRNA, and thus overrides the endonuclease targeting mechanism. Here, we pursued how this protective RNA element functions to maintain mRNA stability. Using affinity purification and mass spectrometry, we identified a set of proteins that associate specifically with the protective element. Although multiple proteins contributed to the escape mechanism, depletion of nucleolin (NCL) most severely impacted protection. NCL was re-localized out of the nucleolus during lytic KSHV infection, and its presence in the cytoplasm was required for protection. After loading onto the IL-6 3' UTR, NCL differentially bound to the translation initiation factor eIF4H. Disrupting this interaction, or depleting eIF4H, reinstated SOX targeting of the RNA, suggesting that interactions between proteins bound to distant regions of the mRNA are important for escape. Finally, we found that the IL-6 3' UTR was also protected against mRNA degradation by the vhs endonuclease encoded by herpes simplex virus, despite the fact that its mechanism of mRNA targeting is distinct from SOX. These findings highlight how a multitude of RNA-protein interactions can impact endonuclease targeting, and identify new features underlying the regulation of the IL-6 mRNA.

Large scale genotype comparison of human papillomavirus E2-host interaction networks provides new insights for e2 molecular functions.

Human Papillomaviruses (HPV) cause widespread infections in humans, resulting in latent infections or diseases ranging from benign hyperplasia to cancers. HPV-induced pathologies result from complex interplays between viral proteins and the host proteome. Given the major public health concern due to HPV-associated cancers, most studies have focused on the early proteins expressed by HPV genotypes with high oncogenic potential (designated high-risk HPV or HR-HPV). To advance the global understanding of HPV pathogenesis, we mapped the virus/host interaction networks of the E2 regulatory protein from 12 genotypes representative of the range of HPV pathogenicity. Large-scale identification of E2-interaction partners was performed by yeast two-hybrid screenings of a HaCaT cDNA library. Based on a high-confidence scoring scheme, a subset of these partners was then validated for pair-wise interaction in mammalian cells with the whole range of the 12 E2 proteins, allowing a comparative interaction analysis. Hierarchical clustering of E2-host interaction profiles mostly recapitulated HPV phylogeny and provides clues to the involvement of E2 in HPV infection. A set of cellular proteins could thus be identified discriminating, among the mucosal HPV, E2 proteins of HR-HPV 16 or 18 from the non-oncogenic genital HPV. The study of the interaction networks revealed a preferential hijacking of highly connected cellular proteins and the targeting of several functional families. These include transcription regulation, regulation of apoptosis, RNA processing, ubiquitination and intracellular trafficking. The present work provides an overview of E2 biological functions across multiple HPV genotypes.

A Balancing Act: The Viral-Host Battle over RNA Binding Proteins.

A defining feature of a productive viral infection is the co-opting of host cell resources for viral replication. Despite the host repertoire of molecular functions and biological counter measures, viruses still subvert host defenses to take control of cellular factors such as RNA binding proteins (RBPs). RBPs are involved in virtually all steps of mRNA life, forming ribonucleoprotein complexes (mRNPs) in a highly ordered and regulated process to control RNA fate and stability in the cell. As such, the hallmark of the viral takeover of a cell is the reshaping of RNA fate to modulate host gene expression and evade immune responses by altering RBP interactions. Here, we provide an extensive review of work in this area, particularly on the duality of the formation of RNP complexes that can be either pro- or antiviral. Overall, in this review, we highlight the various ways viruses co-opt RBPs to regulate RNA stability and modulate the outcome of infection by gathering novel insights gained from research studies in this field.

Case report: Chronic Candida albicans meningitis: a rare entity diagnosed by metagenomic next-generation sequencing.

The aetiology of chronic aseptic meningitis is difficult to establish. Candida meningitis in particular is often diagnosed late, as cerebrospinal fluid (CSF) work-up and imaging findings are nonspecific. A 35-year-old patient with chronic aseptic meningitis, for which repeated microbiological testing of CSF was unrevealing, was finally diagnosed with Candida albicans (C. albicans) meningitis with cauda equina involvement using metagenomic next-generation sequencing (mNGS). This report highlights the diagnostic challenges and the difficulties of treating shunt-associated fungal meningitis.

Training Performance Assessment for Intracranial Aneurysm Clipping Surgery Using a Patient-Specific Mixed-Reality Simulator: A Learning Curve Study.

BACKGROUND AND OBJECTIVES: The value of simulation-based training in medicine and surgery has been widely demonstrated. This study investigates the introduction and use of a new mixed-reality neurosurgical simulator in aneurysm clipping surgery, focusing on the learning curve and performance improvement. METHODS: Five true-scale craniotomy head models replicating patient-specific neuroanatomy, along with a mixed-reality simulator, a neurosurgical microscope, and a set of microsurgical instruments and clips, were used in the operation theater to simulate aneurysm microsurgery. Six neurosurgical residents participated in five video-recorded simulation sessions over 4 months. Complementary learning modalities were implemented between sessions. Thereafter, three blinded analysts reported on residents' use of the microscope, quality of manipulation, aneurysm occlusion, clipping techniques, and aneurysm rupture. Data were also captured regarding training time and clipping attempts. RESULTS: Over the course of training, clipping time and number of clipping attempts decreased significantly (P = .018, P = .032) and the microscopic skills improved (P = .027). Quality of manipulation and aneurysm occlusion scoring improved initially although the trend was interrupted because the spacing between sessions increased. Significant differences in clipping time and attempts were observed between the most and least challenging patient models (P = .005, P = .0125). The least challenging models presented higher rates of occlusion based on indocyanine green angiography evaluation from the simulator. CONCLUSION: The intracranial aneurysm clipping learning curve can be improved by implementing a new mixed-reality simulator in dedicated training programs. The simulator and the models enable comprehensive training under the guidance of a mentor.

Baseline characteristics and outcome of stroke patients after endovascular therapy according to previous symptomatic vascular disease and sex.

Aim: The aim of this study was to investigate baseline characteristics and outcome of patients after endovascular therapy (EVT) for acute large vessel occlusion (LVO) in relation to their history of symptomatic vascular disease and sex. Methods: Consecutive EVT-eligible patients with LVO in the anterior circulation admitted to our stroke center between 04/2015 and 04/2020 were included in this observational cohort study. All patients were treated according to a standardized acute ischaemic stroke (AIS) protocol. Baseline characteristics and successful reperfusion, recurrent/progressive in-hospital ischaemic stroke, symptomatic in-hospital intracranial hemorrhage, death at discharge and at 3 months, and functional outcome at 3 months were analyzed according to previous symptomatic vascular disease and sex. Results: 995 patients with LVO in the anterior circulation (49.4% women, median age 76 years, median admission NIHSS score 14) were included. Patients with multiple vs. no previous vascular events showed higher mortality at discharge (20% vs. 9.3%, age/sex - adjustedOR = 1.43, p = 0.030) and less independency at 3 months (28.8% vs. 48.8%, age/sex - adjustedOR = 0.72, p = 0.020). All patients and men alone with one or multiple vs. patients and men with no previous vascular events showed more recurrent/progressive in-hospital ischaemic strokes (19.9% vs. 6.4% in all patients, age/sex - adjustedOR = 1.76, p = 0.028) (16.7% vs. 5.8% in men, age-adjustedOR = 2.20, p = 0.035). Men vs. women showed more in-hospital symptomatic intracranial hemorrhage among patients with one or multiple vs. no previous vascular events (23.7% vs. 6.6% in men and 15.4% vs. 5.5% in women, OR = 2.32, p = 0.035/age - adjustedOR = 2.36, p = 0.035). Conclusions: Previous vascular events increased the risk of in-hospital complications and poorer outcome in the analyzed patients with EVT-eligible LVO-AIS. Our findings may support risk assessment in these stroke patients and could contribute to the design of future studies.