A multicenter randomized controlled trial indicates that paclitaxel-coated balloons provide no benefit for arteriovenous fistulas.

The role of paclitaxel-coated balloons has been established in the coronary and peripheral arterial circulations with recent interest in the use of paclitaxel-coated balloons to improve patency rates following angioplasty of arteriovenous fistulas. To assess the efficacy of paclitaxel-coated angioplasty balloons to prolong the survival time of target lesion primary patency in arteriovenous fistulas, we designed an investigator-led multi-center randomized controlled trial with follow up time variable for a minimum of one year. Patients with an arteriovenous fistula who were undergoing an angioplasty for a clinical indication were included but patients with one or more lesions outside the treatment segment were excluded. Following successful treatment with a high-pressure balloon, 212 patients were randomized. In the intervention arm, the second component was insertion of a paclitaxel-coated balloon. In the control arm, an identical procedure was followed, but using a standard balloon. The primary endpoint was time to loss of clinically driven target lesion primary patency. Primary analysis showed no significant evidence for a difference in time to end of target lesion primary patency between groups: hazard ratio 1.18 with a 95% confidence interval of 0.78 to 1.79. There were no significant differences for any secondary outcomes, including patency outcomes and adverse events. Thus, our study demonstrated no evidence that paclitaxel-coated balloons provide benefit, following standard care high-pressure balloon angioplasty, in the treatment of arteriovenous fistulas. Hence, in view of the benefit suggested by other trials, the role of paclitaxel-coated angioplasty balloons remains uncertain.

Recovered after an extreme bottleneck and saved by ex situ management: Lessons from the Alagoas curassow (Pauxi mitu [Linnaeus, 1766]; Aves, Galliformes, Cracidae).

A pivotal debate on biodiversity conservation is whether the scarce budgets must be invested in critically endangered taxa or in those with higher chances to survive due to larger population sizes. Addressing the fate of extremely bottlenecked taxa is an ideal way to test this idea, but empirical cases are surprisingly limited. The reintroduction of the extinct-in-the-wild Alagoas curassow (Pauxi mitu) by Brazilian scientists in September 2019 added to the two other known cases of survival to bottlenecks of only two or three individuals. We exploit the reasons why this species has survived, and we report how investments to rescue the Alagoas curassow resulted in the protection of many other taxa, suggesting that in the face of the dramatic number of extinctions expected for the Anthropocene, integration must prevail over a choice.

Identification of a novel TIF-IA-NF-κB nucleolar stress response pathway.

p53 as an effector of nucleolar stress is well defined, but p53 independent mechanisms are largely unknown. Like p53, the NF-κB transcription factor plays a critical role in maintaining cellular homeostasis under stress. Many stresses that stimulate NF-κB also disrupt nucleoli. However, the link between nucleolar function and activation of the NF-κB pathway is as yet unknown. Here we demonstrate that artificial disruption of the PolI complex stimulates NF-κB signalling. Unlike p53 nucleolar stress response, this effect does not appear to be linked to inhibition of rDNA transcription. We show that specific stress stimuli of NF-κB induce degradation of a critical component of the PolI complex, TIF-IA. This degradation precedes activation of NF-κB and is associated with increased nucleolar size. It is mimicked by CDK4 inhibition and is dependent upon a novel pathway involving UBF/p14ARF and S44 of the protein. We show that blocking TIF-IA degradation blocks stress effects on nucleolar size and NF-κB signalling. Finally, using ex vivo culture, we show a strong correlation between degradation of TIF-IA and activation of NF-κB in freshly resected, human colorectal tumours exposed to the chemopreventative agent, aspirin. Together, our study provides compelling evidence for a new, TIF-IA-NF-κB nucleolar stress response pathway that has in vivo relevance and therapeutic implications.

An objective methodology capturing online commodity marketing and other harms.

Increasingly life is lived online, yet little is known about the actual nature and extent of online content that people view due to the difficulty of recording real time exposure. This includes people's exposure to harmful commodity marketing. This study aimed to develop a methodology to assess the nature and extent of exposure to, and engagement with, unhealthy commodity marketing and other public health harms online, particularly children's exposure. A convenience sample of 16 young adult participants (aged 21-29) recorded their device usage for 2 days using Zoom software. Data were coded and analysed to assess the nature and extent of marketing for alcohol, gambling, junk food and smoking products. Four focus groups were conducted with participants to explore their data collection and coding experiences, and results assessed using thematic analysis. The study found that, with some modifications, this method was feasible for gathering real-time objective data from the online world that can be analysed for a range of public health harms, including marketing of unhealthy commodities. Larger studies are recommended to build global evidence for public health action in the online world.

Antibiotic treatment of asymptomatic bacteriuria prior to hip and knee arthroplasty; a systematic review of the literature.

BACKGROUND: There is significant debate as to whether routine antibiotic treatment of asymptomatic bacteriuria (ASB) in arthroplasty patients reduces the risk of subsequent PJI. No previous systematic reviews have been undertaken on this subject. The aim of this systematic review was to investigate whether antibiotic treatment of asymptomatic bacteriuria in arthroplasty patients reduces the risk of prosthetic joint infection and to investigate whether the organisms cultured in peri-operative urine samples are the same as those responsible for subsequent prosthetic joint infections. METHODS: Medline and SCOPUS databases were searched using a systematic search strategy. Inclusion Criteria were that the paper must present data detailing infection rates in patients with asymptomatic bacteriuria versus those without and must provide information on infection rates for ASB patients treated with antibiotics versus those not treated. Non-English Language papers and Conference Abstracts in which a full manuscript was not published were excluded. Two hundred and five papers were returned - three papers were included in the review, comprising 3267 patients. RESULTS: Only 3 studies met the inclusion criteria. The published literature does not support the routine antibiotic treatment of asymptomatic bacteriuria in arthroplasty patients. The organisms responsible for peri-prosthetic joint infection in patients with pre-operative asymptomatic bacteriuria are different from that cultured in their urine during the pre-operative period. This means that, although biologically possible, a direct causal relationship appears extremely unlikely. CONCLUSIONS: The evidence base supporting antibiotic treatment of asymptomatic bacteriuria prior to arthroplasty surgery is weak. Given the lack of evidence to support a direct causal relationship, routine antibiotic treatment of ASB in arthroplasty patients is not justified.

Genetics of CD33 in Alzheimer's disease and acute myeloid leukemia.

The CD33 single-nucleotide polymorphism (SNP) rs3865444 has been associated with the risk of Alzheimer's disease (AD). Rs3865444 is in linkage disequilibrium with rs12459419 which has been associated with efficacy of an acute myeloid leukemia (AML) chemotherapeutic agent based on a CD33 antibody. We seek to evaluate the extent to which CD33 genetics in AD and AML can inform one another and advance human disease therapy. We have previously shown that these SNPs are associated with skipping of CD33 exon 2 in brain mRNA. Here, we report that these CD33 SNPs are associated with exon 2 skipping in leukocytes from AML patients and with a novel CD33 splice variant that retains CD33 intron 1. Each copy of the minor rs12459419T allele decreases prototypic full-length CD33 expression by ∼ 25% and decreases the AD odds ratio by ∼ 0.10. These results suggest that CD33 antagonists may be useful in reducing AD risk. CD33 inhibitors may include humanized CD33 antibodies such as lintuzumab which was safe but ineffective in AML clinical trials. Here, we report that lintuzumab downregulates cell-surface CD33 by 80% in phorbol-ester differentiated U937 cells, at concentrations as low as 10 ng/ml. Overall, we propose a model wherein a modest effect on RNA splicing is sufficient to mediate the CD33 association with AD risk and suggest the potential for an anti-CD33 antibody as an AD-relevant pharmacologic agent.

p300-mediated acetylation of COMMD1 regulates its stability, and the ubiquitylation and nucleolar translocation of the RelA NF-κB subunit.

Nucleolar sequestration of the RelA subunit of nuclear factor (NF)-κB is an important mechanism for regulating NF-κB transcriptional activity. Ubiquitylation, facilitated by COMMD1 (also known as MURR1), acts as a crucial nucleolar-targeting signal for RelA, but how this ubiquitylation is regulated, and how it differs from cytokine-mediated ubiquitylation, which causes proteasomal degradation of RelA, is poorly understood. Here, we report a new role for p300 (also known as EP300) in controlling stimulus-specific ubiquitylation of RelA, through modulation of COMMD1. We show that p300 is required for stress-mediated ubiquitylation and nucleolar translocation of RelA, but that this effect is indirect. We also demonstrate that COMMD1 is acetylated by p300 and that acetylation protects COMMD1 from XIAP-mediated proteosomal degradation. Furthermore, we demonstrate that COMMD1 acetylation is enhanced by aspirin-mediated stress, and that this acetylation is absolutely required for the protein to bind RelA under these conditions. In contrast, tumour necrosis factor (TNF) has no effect on COMMD1 acetylation. Finally, we demonstrate these findings have relevance in a whole tissue setting. These data offer a new paradigm for the regulation of NF-κB transcriptional activity, and the multiple other pathways controlled by COMMD1.

CD33 Alzheimer's risk-altering polymorphism, CD33 expression, and exon 2 splicing.

Genome-wide association studies are identifying novel Alzheimer's disease (AD) risk factors. Elucidating the mechanism underlying these polymorphisms is critical to the validation process and, by identifying rate-limiting steps in AD risk, may yield novel therapeutic targets. Here, we elucidate the mechanism of action of the AD-associated polymorphism rs3865444 in the promoter of CD33, a member of the sialic acid-binding Ig-superfamily of lectins (SIGLECs). Immunostaining established that CD33 is expressed in microglia in human brain. Consistent with this finding, CD33 mRNA expression correlated well with expression of the microglial genes CD11b and AIF-1 and was modestly increased with AD status and the rs3865444C AD-risk allele. Analysis of CD33 isoforms identified a common isoform lacking exon 2 (D2-CD33). The proportion of CD33 expressed as D2-CD33 correlated robustly with rs3865444 genotype. Because rs3865444 is in the CD33 promoter region, we sought the functional polymorphism by sequencing CD33 from the promoter through exon 4. We identified a single polymorphism that is coinherited with rs3865444, i.e., rs12459419 in exon 2. Minigene RNA splicing studies in BV2 microglial cells established that rs12459419 is a functional single nucleotide polymorphism (SNP) that modulates exon 2 splicing efficiency. Thus, our primary findings are that CD33 is a microglial mRNA and that rs3865444 is a proxy SNP for rs12459419 that modulates CD33 exon 2 splicing. Exon 2 encodes the CD33 IgV domain that typically mediates sialic acid binding in SIGLEC family members. In summary, these results suggest a novel model wherein SNP-modulated RNA splicing modulates CD33 function and, thereby, AD risk.

Synthesis of the 6-azaindole containing HIV-1 attachment inhibitor pro-drug, BMS-663068.

The development of a short and efficient synthesis of a complex 6-azaindole, BMS-663068, is described. Construction of the 6-azaindole core is quickly accomplished starting from a simple pyrrole, via a regioselective Friedel-Crafts acylation, Pictet-Spengler cyclization, and a radical-mediated aromatization. The synthesis leverages an unusual heterocyclic N-oxide α-bromination to functionalize a critical C-H bond, enabling a highly regioselective copper-mediated Ullmann-Goldberg-Buchwald coupling to install a challenging triazole substituent. This strategy resulted in an efficient 11 step linear synthesis of this complex clinical candidate.

Expression of INPP5D Isoforms in Human Brain: Impact of Alzheimer's Disease Neuropathology and Genetics.

The single nucleotide polymorphisms rs35349669 and rs10933431 within Inositol Polyphosphate-5-Phosphatase D (INPP5D) are strongly associated with Alzheimer's Disease risk. To better understand INPP5D expression in the brain, we investigated INPP5D isoform expression as a function of rs35349669 and rs10933431, as well as Alzheimer's disease neuropathology, by qPCR and isoform-specific primers. In addition, INPP5D allelic expression imbalance was evaluated relative to rs1141328 within exon 1. Expression of INPP5D isoforms associated with transcription start sites in exon 1 and intron 14 was increased in individuals with high Alzheimer's disease neuropathology. In addition, a novel variant with 47bp lacking from exon 12 increased expression in Alzheimer's Disease brains, accounting for 13% of total INPP5D expression, and was found to undergo nonsense-mediated decay. Although inter-individual variation obscured a possible polymorphism effect on INPP5D isoform expression as measured by qPCR, rs35349669 was associated with rs1141328 allelic expression imbalance, suggesting that rs35349669 is significantly associated with full-length INPP5D isoform expression. In summary, expression of INPP5D isoforms with start sites in exon 1 and intron 14 are increased in brains with high Alzheimer's Disease neuropathology, a novel isoform lacking the phosphatase domain was significantly increased with the disease, and the polymorphism rs35349669 correlates with allele-specific full-length INPP5D expression.

Skipping of FCER1G Exon 2 Is Common in Human Brain But Not Associated with the Alzheimer's Disease Genetic Risk Factor rs2070902.

Background: Understanding the mechanisms whereby genetic variants influence the risk of Alzheimer's disease (AD) may provide insights into treatments that could reduce AD risk. Objective: Here, we sought to test the hypothesis that a single nucleotide polymorphism (SNP) associated with AD risk, rs2070902, influences splicing of FCER1G exon 2. Methods: AD and non-AD brain samples were analyzed for FCER1G expression by genotyping, immunohistochemistry, immunofluorescence, and qPCR. Results: The protein encoded by FCER1G, FcRγ, is robustly expressed in microglia in both AD and non-AD brain. The FCER1G isoform lacking exon 2 (D2-FCER1G) was readily detectable. Moreover, the proportion of FCER1G expressed as this isoform was increased in brains with high AD neuropathology. However, the proportion of FCER1G expressed as the D2-FCER1G isoform was not associated with rs2070902 genotype. Conclusions: In summary, the proportion of FCER1G expressed as the D2-FCER1G isoform is increased with AD neuropathology but is not associated with rs2070902.

Identification and Quantitation of Novel ABI3 Isoforms Relative to Alzheimer's Disease Genetics and Neuropathology.

Elucidating the actions of genetic polymorphisms associated with the risk of Alzheimer's disease (AD) may provide novel insights into underlying mechanisms. Two polymorphisms have implicated ABI3 as a modulator of AD risk. Here, we sought to identify ABI3 isoforms expressed in human AD and non-AD brain, quantify the more abundant isoforms as a function of AD genetics and neuropathology, and provide an initial in vitro characterization of the proteins produced by these novel isoforms. We report that ABI3 expression is increased with AD neuropathology but not associated with AD genetics. Single-cell RNAseq of APP/PS1 mice showed that Abi3 is primarily expressed by microglia, including disease-associated microglia. In human brain, several novel ABI3 isoforms were identified, including isoforms with partial or complete loss of exon 6. Expression of these isoforms correlated tightly with total ABI3 expression but were not influenced by AD genetics. Lastly, we performed an initial characterization of these isoforms in transfected cells and found that, while full-length ABI3 was expressed in a dispersed punctate fashion within the cytosol, isoforms lacking most or all of exon six tended to form extensive protein aggregates. In summary, ABI3 expression is restricted to microglia, is increased with Alzheimer's neuropathology, and includes several isoforms that display a variable tendency to aggregate when expressed in vitro.

Conversation dynamics in a multiplayer video game with knowledge asymmetry.

Despite the challenges associated with virtually mediated communication, remote collaboration is a defining characteristic of online multiplayer gaming communities. Inspired by the teamwork exhibited by players in first-person shooter games, this study investigated the verbal and behavioral coordination of four-player teams playing a cooperative online video game. The game, Desert Herding, involved teams consisting of three ground players and one drone operator tasked to locate, corral, and contain evasive robot agents scattered across a large desert environment. Ground players could move throughout the environment, while the drone operator's role was akin to that of a "spectator" with a bird's-eye view, with access to veridical information of the locations of teammates and the to-be-corralled agents. Categorical recurrence quantification analysis (catRQA) was used to measure the communication dynamics of teams as they completed the task. Demands on coordination were manipulated by varying the ground players' ability to observe the environment with the use of game "fog." Results show that catRQA was sensitive to changes to task visibility, with reductions in task visibility reorganizing how participants conversed during the game to maintain team situation awareness. The results are discussed in the context of future work that can address how team coordination can be augmented with the inclusion of artificial agents, as synthetic teammates.

An Alternatively Spliced TREM2 Isoform Lacking the Ligand Binding Domain is Expressed in Human Brain.

BACKGROUND: Genetic variants in TREM2 are strongly associated with Alzheimer's disease (AD) risk but alternative splicing in TREM2 transcripts has not been comprehensively described. OBJECTIVE: Recognizing that alternative splice variants can result in reduced gene expression and/or altered function, we sought to fully characterize splice variation in TREM2. METHODS: Human anterior cingulate autopsy tissue from 61 donors was used for end-point and quantitative PCR and western blotting to identify and quantify novel TREM2 isoforms. RESULTS: In addition to previously described transcripts lacking exon 3 or exon 4, or retaining part of intron 3, we identified novel isoforms lacking exon 2, along with isoforms lacking multiple exons. Isoforms lacking exon 2 were predominant at approximately 10% of TREM2 mRNA in the brain. Expression of TREM2 and frequency of exon 2 skipping did not differ between AD samples and non-AD controls (p = 0.1268 and p = 0.4909, respectively). Further, these novel splice isoforms were also observed across multiple tissues with similar frequency (range 5.3 -13.0%). We found that the exon 2 skipped isoform D2-TREM2 is translated to protein and localizes similarly to full-length TREM2 protein, that both proteins are primarily retained in the Golgi complex, and that D2-TREM2 is expressed in AD and non-AD brain. CONCLUSION: Since the TREM2 ligand binding domain is encoded by exon 2, and skipping this exon retains reading frame while conserving localization, we hypothesize that D2-TREM2 acts as an inhibitor of TREM2 and targeting TREM2 splicing may be a novel therapeutic pathway for AD.

Assessing Team Effectiveness by How Players Structure Their Search in a First-Person Multiplayer Video Game.

People working as a team can achieve more than when working alone due to a team's ability to parallelize the completion of tasks. In collaborative search tasks, this necessitates the formation of effective division of labor strategies to minimize redundancies in search. For such strategies to be developed, team members need to perceive the task's relevant components and how they evolve over time, as well as an understanding of what others will do so that they can structure their own behavior to contribute to the team's goal. This study explored whether the capacity for team members to coordinate effectively can be related to how participants structure their search behaviors in an online multiplayer collaborative search task. Our results demonstrated that the structure of search behavior, quantified using detrended fluctuation analysis, was sensitive to contextual factors that limit a participant's ability to gather information. Further, increases in the persistence of movement fluctuations during search behavior were found as teams developed more effective coordinative strategies and were associated with better task performance.

Arthroscopic reconstruction of the ligamentum teres.

We describe a case of arthroscopic reconstruction of the ligamentum teres using a novel technique. This technique is both simple and reproducible. We believe it to be a useful addition to the procedures available to the arthroscopic hip surgeon.

Analysis of Genetic Variants Associated with Levels of Immune Modulating Proteins for Impact on Alzheimer's Disease Risk Reveal a Potential Role for SIGLEC14.

Genome-wide association studies (GWAS) have identified immune-related genes as risk factors for Alzheimer's disease (AD), including TREM2 and CD33, frequently passing a stringent false-discovery rate. These genes either encode or signal through immunomodulatory tyrosine-phosphorylated inhibitory motifs (ITIMs) or activation motifs (ITAMs) and govern processes critical to AD pathology, such as inflammation and amyloid phagocytosis. To investigate whether additional ITIM and ITAM-containing family members may contribute to AD risk and be overlooked due to the stringent multiple testing in GWAS, we combined protein quantitative trait loci (pQTL) data from a recent plasma proteomics study with AD associations in a recent GWAS. We found that pQTLs for genes encoding ITIM/ITAM family members were more frequently associated with AD than those for non-ITIM/ITAM genes. Further testing of one family member, SIGLEC14 which encodes an ITAM, uncovered substantial copy number variations, identified an SNP as a proxy for gene deletion, and found that gene expression correlates significantly with gene deletion. We also found that SIGLEC14 deletion increases the expression of SIGLEC5, an ITIM. We conclude that many genes in this ITIM/ITAM family likely impact AD risk, and that complex genetics including copy number variation, opposing function of encoded proteins, and coupled gene expression may mask these AD risk associations at the genome-wide level.

Expression and regulation of a low-density lipoprotein receptor exon 12 splice variant.

As low-density lipoprotein receptor (LDLR) contributes to cholesterol and amyloid beta homeostasis, insights into LDLR regulation may facilitate our understanding of cardiovascular disease and Alzheimer's disease. Previously, we identified LDLR isoforms that lacked exon 12 or exons 11-12 and that are predicted to encode soluble, dominant negative, LDLR. Moreover, these isoforms were associated with rs688, an exon 12 polymorphism that was associated with LDL-cholesterol and Alzheimer's disease risk. In this study, we present evidence that although the truncated LDLR isoforms are translated in vitro, they represent < 0.1% of CSF proteins. As these LDLR isoforms likely represent a loss of mRNA-encoding functional LDLR, we then focused upon identifying intron-exon boundary and exonic splicing enhancer elements critical to splicing. Exon 12 inclusion is enhanced by altering the 5' splice site in intron 12 towards a consensus splice donor sequence, consistent with its being a weak 5' splice site. Additionally, of the nine evolutionarily conserved putative splicing enhancer regions within exon 12, two regions that flank rs688 were critical to exon 12 inclusion. Overall, these results suggest that LDLR splice variants represent a loss of mRNA encoding functional LDLR and provide insights into the regulatory elements critical for LDLR exon 12 splicing.

Sex-dependent association of a common low-density lipoprotein receptor polymorphism with RNA splicing efficiency in the brain and Alzheimer's disease.

Since apoE allele status is the predominant Alzheimer's disease (AD) genetic risk factor, functional single nucleotide polymorphisms (SNPs) in brain apoE receptors represent excellent candidates for association with AD. Recently, we identified a SNP, rs688, as modulating the splicing efficiency of low-density lipoprotein receptor (LDLR) exon 12 in female human liver and in minigene-transfected HepG2 cells. Moreover, the rs688T minor allele was associated with significantly higher LDL and total cholesterol in women within the Framingham Offspring Study cohort. Since LDLR is a major apoE receptor in the brain, we hypothesized that rs688 modulates LDLR splicing in neural tissues and associates with AD. To evaluate this hypothesis, we first transfected LDLR minigenes into SH-SY5Y neuroblastoma cells and found that the rs688T allele reduces exon 12 inclusion in this neural model. We then evaluated the association of rs688 allele with exon 12 splicing efficiency in vivo by quantifying LDLR splicing in human anterior cingulate tissue obtained at autopsy; the rs688T allele is associated with decreased LDLR exon 12 splicing efficiency in aged males, but not females. Lastly, we evaluated whether rs688 associates with AD by genotyping DNA from 1457 men and 2055 women drawn from three case-control series. The rs688T/T genotype was associated with increased AD odds in males [recessive model, odds ratio (OR) of 1.49, 95% confidence interval (CI) of 1.13-1.97, uncorrected P = 0.005], but not in females. In summary, these studies identify a functional apoE receptor SNP that is associated with AD in a sex-dependent fashion.

A Randomised Controlled Trial of Local Infiltration Analgesia Versus Femoral Nerve Block for Postoperative Analgesia Following Total Knee Arthroplasty.

Background Total knee replacement is often associated with significant postoperative pain. Although the use of a femoral nerve block is well-established, local infiltration analgesia has gained popularity in recent years. We compared single-shot local infiltration analgesia with a single-shot femoral nerve block for patients undergoing primary total knee arthroplasty. Methods A total of 194 patients were randomised to receive either local infiltration analgesia (150 ml bupivacaine 0.067% with adrenaline) or a femoral nerve block (20 ml 0.375% levobupivacaine). Both groups received spinal anaesthesia. The primary outcome measure was the total morphine consumption. Secondary outcome measures included: post-operative pain scores, rehabilitation goals, readiness for discharge, and physical, mental, and functional outcomes, including the Oxford Knee Score (OKS). Results A total of 69 patients in the local infiltration analgesia group and 79 patients in the femoral nerve block group were analysed. Median total morphine consumption was significantly greater in the local infiltration analgesia group as compared to the femoral nerve block group (54.67 mg vs 45 mg, respectively, p=0.0388). The post-operative OKS at six weeks was slightly more improved for the femoral nerve block group than for local infiltration analgesia (12.5 vs 9 point median improvements for the femoral nerve block and local infiltration analgesia groups, respectively, p=0.0261). There were no statistically significant differences in other secondary outcome measures. Conclusion A single-shot femoral nerve block significantly reduces the opioid requirement for primary total knee arthroplasty but is otherwise comparable to single-shot local infiltration analgesia.