Directing reaction pathways via in situ control of active site geometries in PdAu single-atom alloy catalysts

The atomic scale structure of the active sites in heterogeneous catalysts is central to their reactivity and selectivity. Therefore, understanding active site stability and evolution under different reaction conditions is key to the design of efficient and robust catalysts. Herein we describe theoretical calculations which predict that carbon monoxide can be used to stabilize different active site geometries in bimetallic alloys and then demonstrate experimentally that the same PdAu bimetallic catalyst can be transitioned between a single-atom alloy and a Pd cluster phase. Each state of the catalyst exhibits distinct selectivity for the dehydrogenation of ethanol reaction with the single-atom alloy phase exhibiting high selectivity to acetaldehyde and hydrogen versus a range of products from Pd clusters. First-principles based Monte Carlo calculations explain the origin of this active site ensemble size tuning effect, and this work serves as a demonstration of what should be a general phenomenon that enables in situ control over catalyst selectivity

From presence to consciousness through virtual reality

Immersive virtual environments can break the deep, everyday connection between where our senses tell us we are and where we are actually located and whom we are with. The concept of 'presence' refers to the phenomenon of behaving and feeling as if we are in the virtual world created by computer displays. In this article, we argue that presence is worthy of study by neuroscientists, and that it might aid the study of perception and consciousness

Estimation of Plasmodium falciparum Transmission Intensity in Lilongwe, Malawi, by Microscopy, Rapid Diagnostic Testing, and Nucleic Acid Detection.

: Estimates of malaria transmission intensity (MTI) typically rely upon microscopy or rapid diagnostic testing (RDT). However, these methods are less sensitive than nucleic acid amplification techniques and may underestimate parasite prevalence. We compared microscopy, RDT, and polymerase chain reaction (PCR) for the diagnosis of Plasmodium falciparum parasitemia as part of an MTI study of 800 children and adults conducted in Lilongwe, Malawi. PCR detected more cases of parasitemia than microscopy or RDT. Age less than 5 years predicted parasitemia detected by PCR alone (adjusted odds ratio = 1.61, 95% confidence interval = 1.09-2.38, Wald P = 0.02). In addition, we identified one P. falciparum parasite with a false-negative RDT result due to a suspected deletion of the histidine-rich protein 2 (hrp2) gene and used a novel, ultrasensitive PCR assay to detect low-level parasitemia missed by traditional PCR. Molecular methods should be considered for use in future transmission studies as a supplement to RDT or microscopy.<br/

Lung epithelial protein disulfide isomerase A3 (PDIA3) plays an important role in influenza infection, inflammation, and airway mechanics

© 2019 Protein disulfide isomerases (PDI) are a family of redox chaperones that catalyze formation or isomerization of disulfide bonds in proteins. Previous studies have shown that one member, PDIA3, interacts with influenza A virus (IAV) hemagglutinin (HA), and this interaction is required for efficient oxidative folding of HA in vitro. However, it is unknown whether these host-viral protein interactions occur during active infection and whether such interactions represent a putative target for the treatment of influenza infection. Here we show that PDIA3 is specifically upregulated in IAV-infected mouse or human lung epithelial cells and PDIA3 directly interacts with IAV-HA. Treatment with a PDI inhibitor, LOC14 inhibited PDIA3 activity in lung epithelial cells, decreased intramolecular disulfide bonds and subsequent oligomerization (maturation) of HA in both H1N1 (A/PR8/34) and H3N2 (X31, A/Aichi/68) infected lung epithelial cells. These reduced disulfide bond formation significantly decreased viral burden, and also pro-inflammatory responses from lung epithelial cells. Lung epithelial-specific deletion of PDIA3 in mice resulted in a significant decrease in viral burden and lung inflammatory-immune markers upon IAV infection, as well as significantly improved airway mechanics. Taken together, these results indicate that PDIA3 is required for effective influenza pathogenesis in vivo, and pharmacological inhibition of PDIs represents a promising new anti-influenza therapeutic strategy during pandemic and severe influenza seasons

Q methodology and a Delphi poll: a useful approach to researching a narrative approach to therapy

Q methodology and a Delphi poll combined qualitative and quantitative methods to explore definitions of White and Epston's (1990) narrative approach to therapy among a group of UK practitioners. A Delphi poll was used to generate statements about narrative therapy. The piloting of statements by the Delphi panel identified agreement about theoretical ideas underpinning narrative therapy and certain key practices. A wider group of practitioners ranked the statements in a Q sort and made qualitative comments about their sorting. Quantitative methods (principal components analysis) were used to extract eight accounts of narrative therapy, five of which are qualitatively analysed in this paper. Agreement and differences were identified across a range of issues, including the social construction of narratives, privileging a political stance or narrative techniques and the relationship with other therapies, specifically systemic psychotherapy. Q methodology, combined with the Delphi poll, was a unique and innovative feature of this study

Comparative Effectiveness of Adalimumab vs Tofacitinib in Patients With Rheumatoid Arthritis in Australia

Importance: There is a need for observational studies to supplement evidence from clinical trials, and the target trial emulation (TTE) framework can help avoid biases that can be introduced when treatments are compared crudely using observational data by applying design principles for randomized clinical trials. Adalimumab (ADA) and tofacitinib (TOF) were shown to be equivalent in patients with rheumatoid arthritis (RA) in a randomized clinical trial, but to our knowledge, these drugs have not been compared head-to-head using routinely collected clinical data and the TTE framework. Objective: To emulate a randomized clinical trial comparing ADA vs TOF in patients with RA who were new users of a biologic or targeted synthetic disease-modifying antirheumatic drug (b/tsDMARD). Design, Setting, and Participants: This comparative effectiveness study emulating a randomized clinical trial of ADA vs TOF included Australian adults aged 18 years or older with RA in the Optimising Patient Outcomes in Australian Rheumatology (OPAL) data set. Patients were included if they initiated ADA or TOF between October 1, 2015, and April 1, 2021; were new b/tsDMARD users; and had at least 1 component of the disease activity score in 28 joints using C-reactive protein (DAS28-CRP) recorded at baseline or during follow-up. Intervention: Treatment with either ADA (40 mg every 14 days) or TOF (10 mg daily). Main Outcomes and Measures: The main outcome was the estimated average treatment effect, defined as the difference in mean DAS28-CRP among patients receiving TOF compared with those receiving ADA at 3 and 9 months after initiating treatment. Missing DAS28-CRP data were multiply imputed. Stable balancing weights were used to account for nonrandomized treatment assignment. Results: A total of 842 patients were identified, including 569 treated with ADA (387 [68.0%] female; median age, 56 years [IQR, 47-66 years]) and 273 treated with TOF (201 [73.6%] female; median age, 59 years [IQR, 51-68 years]). After applying stable balancing weights, mean DAS28-CRP in the ADA group was 5.3 (95% CI, 5.2-5.4) at baseline, 2.6 (95% CI, 2.5-2.7) at 3 months, and 2.3 (95% CI, 2.2-2.4) at 9 months; in the TOF group, it was 5.3 (95% CI, 5.2-5.4) at baseline, 2.4 (95% CI, 2.2-2.5) at 3 months, and 2.3 (95% CI, 2.1-2.4) at 9 months. The estimated average treatment effect was -0.2 (95% CI, -0.4 to -0.03; P = .02) at 3 months and -0.03 (95% CI, -0.2 to 0.1; P = .60) at 9 months. Conclusions and Relevance: In this study, there was a modest but statistically significant reduction in DAS28-CRP at 3 months for patients receiving TOF compared with those receiving ADA and no difference between treatment groups at 9 months. Three months of treatment with either drug led to clinically relevant average reductions in mean DAS28-CRP, consistent with remission

Diagnosis and aetiology of congenital muscular dystrophy: we are halfway there

OBJECTIVES: To evaluate the diagnostic outcomes in a large cohort of congenital muscular dystrophy (CMD) patients using traditional and Next Generation Sequencing (NGS) technologies. METHODS: 123 CMD patients were investigated using the traditional approaches of histology, immunohistochemical analysis of muscle biopsy and candidate gene sequencing. Undiagnosed patients available for further testing were investigated using NGS. RESULTS: Muscle biopsy and immunohistochemical analysis found deficiencies of laminin α2, α-dystroglycan or collagen VI in 50% of patients. Candidate gene sequencing and chromosomal microarray established a genetic diagnosis in 32% (39/123). Of 85 patients presenting in the last 20 years, 28 of 51 who lacked a confirmed genetic diagnosis (55%) consented to NGS studies, leading to confirmed diagnoses in a further 11 patients. Using the combination of approaches, a confirmed genetic diagnosis was achieved in 51% (43/85). The diagnoses within the cohort were heterogeneous. 45/59 probands with confirmed or probable diagnoses had variants in genes known to cause CMD (76%), and 11/59 (19%) had variants in genes associated with congenital myopathies, reflecting overlapping features of these conditions. One patient had a congenital myasthenic syndrome and two had microdeletions. Within the cohort, five patients had variants in novel (PIGY and GMPPB) or recently published genes (GFPT1 and MICU1) and seven had variants in TTN or RYR1; large genes that are technically difficult to Sanger sequence. INTERPRETATION: These data support NGS as a first-line tool for genetic evaluation of patients with a clinical phenotype suggestive of CMD, with muscle biopsy reserved as a second-tier investigation. This article is protected by copyright. All rights reserved

Conjugated bile acids attenuate allergen-induced airway inflammation and hyperresposiveness by inhibiting UPR transducers

© 2019 American Society for Clinical Investigation. Conjugated bile acids (CBAs), such as tauroursodeoxycholic acid (TUDCA), are known to resolve the inflammatory and unfolded protein response (UPR) in inflammatory diseases, such as asthma. Whether CBAs exert their beneficial effects on allergic airway responses via 1 arm or several arms of the UPR, or alternatively through the signaling pathways for conserved bile acid receptor, remains largely unknown. We used a house dust mite-induced (HDM-induced) murine model of asthma to evaluate and compare the effects of 5 CBAs and 1 unconjugated bile acid in attenuating allergen-induced UPR and airway responses. Expression of UPRassociated transcripts was assessed in airway brushings from human patients with asthma and healthy subjects. Here we show that CBAs, such as alanyl β-muricholic acid (AβM) and TUDCA, significantly decreased inflammatory, immune, and cytokine responses; mucus metaplasia; and airway hyperresponsiveness, as compared with other CBAs in a model of allergic airway disease. CBAs predominantly bind to activating transcription factor 6α (ATF6α) compared with the other canonical transducers of the UPR, subsequently decreasing allergen-induced UPR activation and resolving allergic airway disease, without significant activation of the bile acid receptors. TUDCA and AβM also attenuated other HDM-induced ER stress markers in the lungs of allergic mice. Quantitative mRNA analysis of airway epithelial brushings from human subjects demonstrated that several ATF6α-related transcripts were significantly upregulated in patients with asthma compared with healthy subjects. Collectively, these results demonstrate that CBA-based therapy potently inhibits the allergen-induced UPR and allergic airway disease in mice via preferential binding of the canonical transducer of the UPR, ATF6α. These results potentially suggest a novel avenue to treat allergic asthma using select CBAs

Unexpected Fine-Scale Population Structure in a Broadcast-Spawning Antarctic Marine Mollusc

Several recent empirical studies have challenged the prevailing dogma that broadcast-spawning species exhibit little or no population genetic structure by documenting genetic discontinuities associated with large-scale oceanographic features. However, relatively few studies have explored patterns of genetic differentiation over fine spatial scales. Consequently, we used a hierarchical sampling design to investigate the basis of a weak but significant genetic difference previously reported between Antarctic limpets (Nacella concinna) sampled from Adelaide and Galindez Islands near the base of the Antarctic Peninsula. Three sites within Ryder Bay, Adelaide Island (Rothera Point, Leonie and Anchorage Islands) were each sub-sampled three times, yielding a total of 405 samples that were genotyped at 155 informative Amplified Fragment Length Polymorphisms (AFLPs). Contrary to our initial expectations, limpets from Anchorage Island were found to be subtly, but significantly distinct from those sampled from the other sites. This suggests that local processes may play an important role in generating fine-scale population structure even in species with excellent dispersal capabilities, and highlights the importance of sampling at multiple spatial scales in population genetic surveys