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Abstract Minor changes to complex structures can exert major influences on synthesis strategy and functional properties. Here we explore two parallel series of picrotoxinin (PXN, 1) analogs and identify leads with selectivity between mammalian and insect ion channels. These are the first SAR studies of PXN despite its >100-year history and are made possible by advances in total synthesis. We observe a remarkable stabilizing effect of a C5 methyl, which completely blocks C15 alcoholysis via destabilization of an intermediate twist-boat conformer; suppression of this secondary hydrolysis pathway increases half-life in plasma. C5 methylation also decreases potency against vertebrate ion channels (γ-Aminobutyric acid type A (GABAA) receptors) but maintains or increases antagonism of homologous invertebrate GABA-gated chloride channels (resistance to dieldrin (RDL) receptors). Optimal 5MePXN analogs appear to change the PXN binding pose within GABAARs by disruption of a hydrogen bond network. These discoveries were made possible by the lower synthetic burden of 5MePXN (2) and were illuminated by the parallel analog series, which allowed characterization of the role of the synthetically simplifying C5 methyl in channel selectivity. These are the first SAR studies to identify changes to PXN that increase the GABAA-RDL selectivity index.

Abstract Background The harsh conditions of high-altitude environments are known to drive the evolution of physiological and morphological traits in endothermic animals. These conditions are expected to result in the adaptive evolution of protein coding genes encoded in mitochondrial genomes that are vital for the oxidative phosphorylation pathway. In this study, we formally tested for signatures of adaptive evolution on mitochondrial protein coding genes in Tapirus pinchaque and other odd-toed ungulates inhabiting high-elevation environments. Results The AT-rich mitochondrial genome of T. pinchaque is 16,750 bp long. A phylomitogenomic analysis supports the monophyly of the genus Tapirus and families in the Perissodactyla. The ratio of non-synonymous to synonymous substitutions demonstrated that all mitochondrial genes undergo purifying selection in T. pinchaque and other odd ungulates living at high elevations. Over this negative background selection, Branch Models suggested that cox3 and nad6 might be undergoing stronger purifying selection than other mitochondrial protein coding genes. Furthermore, Site Models suggested that one and four sites in nad2 and nad5, respectively, could be experiencing positive selection. However, these results were supported by Likelihood Ratio Tests but not Bayesian Empirical Bayes posterior probabilities. Additional analyses (in DataMonkey) indicated a relaxation of selection strength in nad6, evidence of episodic diversifying selection in cob, and revealed episodic positive/diversifying selection signatures for two sites in nad1, and one site each in nad2 and nad4. Conclusion The mitochondrial genome of T. pinchaque is an important genomic resource for conservation of this species and this study contributes to the understanding of adaptive evolution of mitochondrial protein coding genes in odd-toed ungulates inhabiting high-altitude environments.

The global cost-benefit analysis of pesticide use during the last 30 years has been characterized by a significant increase during the period from 1990 to 2007 followed by a decline. This observation can be attributed to several factors including, but not limited to, pest resistance, lack of novelty with respect to modes of action or classes of chemistry, and regulatory action. Due to current and projected increases of the global population, it is evident that the demand for food, and consequently, the usage of pesticides to improve yields will increase. Addressing these challenges and needs while promoting new crop protection agents through an increasingly stringent regulatory landscape requires the development and integration of infrastructures for innovative, cost- and time-effective discovery and development of novel and sustainable molecules. Significant advances in artificial intelligence (AI) and cheminformatics over the last two decades have improved the decision-making power of research scientists in the discovery of bioactive molecules. AI- and cheminformatics-driven molecule discovery offers the opportunity of moving experiments from the greenhouse to a virtual environment where thousands to billions of molecules can be investigated at a rapid pace, providing unbiased hypothesis for lead generation, optimization, and effective suggestions for compound synthesis and testing. To date, this is illustrated to a far lesser extent in the publicly available agrochemical research literature compared to drug discovery. In this review, we provide an overview of the crop protection discovery pipeline and how traditional, cheminformatics, and AI technologies can help to address the needs and challenges of agrochemical discovery towards rapidly developing novel and more sustainable products.

Inflammation is associated with the pathogenesis of myelodysplastic syndromes (MDS) and emerging evidence suggests that MDS hematopoietic stem and progenitor cells (HSPC) exhibit an altered response to inflammation. Deletion of chromosome 5 (del(5q)) is the most common chromosomal abnormality in MDS. Although this MDS subtype contains several haploinsufficient genes that impact innate immune signaling, the effects of inflammation on del(5q) MDS HSPC remains undefined. Utilizing a model of del(5q)-like MDS, inhibiting the IRAK1/4-TRAF6 axis improved cytopenias, suggesting that activation of innate immune pathways contributes to certain clinical features underlying the pathogenesis of low-risk MDS. However, low-grade inflammation in the del(5q)-like MDS model did not contribute to more severe disease but instead impaired the del(5q)-like HSPC as indicated by their diminished numbers, premature attrition and increased p53 expression. Del(5q)-like HSPC exposed to inflammation became less quiescent, but without affecting cell viability. Unexpectedly, the reduced cellular quiescence of del(5q) HSPC exposed to inflammation was restored by p53 deletion. These findings uncovered that inflammation confers a competitive advantage of functionally defective del(5q) HSPC upon loss of p53. Since TP53 mutations are enriched in del(5q) AML following an MDS diagnosis, increased p53 activation in del(5q) MDS HSPC due to inflammation may create a selective pressure for genetic inactivation of p53 or expansion of a pre-existing TP53-mutant clone.

Ocular albinism type 1 (OA), caused by mutations in the OA1 gene, encodes a G-protein coupled receptor, OA1, localized in melanosomal membranes of the retinal pigment epithelium (RPE). This disorder is characterized by both RPE macro-melanosomes and abnormal decussation of ganglion cell axons at the brain's optic chiasm. We demonstrated previously that Oa1 specifically activates Gαi3, which also signals in the Oa1 transduction pathway that regulates melanosomal biogenesis. In this study, we screened the human Gαi3 gene, GNAI3, in DNA samples from 26 patients who had all clinical characteristics of OA but in whom a specific mutation in the OA1 gene had not been found, and in 6 normal control individuals. Using the Agilent HaloPlex Target Enrichment System and next-generation sequencing (NGS) on the Illumina MiSeq platform, we identified 518 variants after rigorous filtering. Many of these variants were corroborated by Sanger sequencing. Overall, 98.8% coverage of the GNAI3 gene was obtained by the HaloPlex amplicons. Of all variants, 6 non-synonymous and 3 synonymous were in exons, 41 in a non-coding exon embedded in the 3' untranslated region (UTR), 6 in the 5' UTR, and 462 in introns. These variants included novel SNVs, insertions, deletions, and a frameshift mutation. All were found in at least one patient but none in control samples. Using computational methods, we modeled the GNAI3 protein and its non-synonymous exonic mutations and determined that several of these may be the cause of disease in the patients studied. Thus, we have identified GNAI3 as a second gene possibly responsible for X-linked ocular albinism.

Noble metal oxides such as ruthenium dioxide are highly active electrocatalysts for anodic reactions in acidic electrolytes, but dissolution during electrochemical operation impedes wide-scale applications in renewable energy technologies. Improving the fundamental understanding of the dissolution dynamics of application-relevant morphologies such as nanocrystals is critical for the grid-scale implementation of these materials. Herein, we report the nanoscale heterogeneity observed via liquid-phase transmission electron microscopy during ruthenium dioxide nanocrystal dissolution under oxidizing conditions. Single-crystalline ruthenium dioxide nanocrystals enabled the direct observation of dissolution along different crystallographic facets, allowing an unprecedented direct comparison of crystal facet stability. The nanoscale observations revealed substantial heterogeneity in the relative stability of crystallographic facets across different nanocrystals, attributed to the nanoscale strains present in these crystals. These findings highlight the importance of nanoscale heterogeneity in determining macroscale properties such as electrocatalyst stability and provide a characterization methodology that can be integrated into next-generation electrocatalyst discovery efforts.

Background: Over-the-counter (OTC) hearing aids were recently approved for sale in the United States. Research has shown that consumers prefer hearing devices that match their skin color because these devices are less noticeable. Colorism is discrimination against individuals with relatively darker skin that manifests in "skin-color" product offerings as products being offered primarily in relatively lighter colors., Methods: This study compared images of U.S. Food and Drug Administration (FDA)-registered over-the-counter hearing aids to a range of human skin colors., Results: Most over-the-counter hearing aids are only offered in relatively lighter beige colors. Few over-the-counter hearing aids are available in darker skin colors., Conclusions: These findings may represent structural bias, preventing equitable access to darker skin-color OTC hearing aids for individuals with darker skin.

Purpose: Students in audiology clinical doctorate programs in the United States are required to participate in direct patient care under the supervision of a licensed precepting audiologist during their schooling. Audiology student clinicians commonly rotate through a variety of clinical settings with their own organizational structure, policies, and precepting clinicians. Systemic prejudice and stigma cause many of these student clinicians to experience bigotry from the patients they work with., Method: This review discusses the populations of audiology students at highest risk of patient bigotry and discusses the intersectionality of students with several historically marginalized identities., Results: Little scholarship exists in the field of audiology on the bigotry that graduate student clinicians experience. The effects of bigotry are reviewed, and practical guidance on preparing for and responding to bigotry from patients is provided., Conclusions: As health care workers, these students are essential workers contributing to the health and health care of the population, making their well-being a critical public health concern. Bigotry from others has been shown to contribute to mental illness, burnout, and poorer physical health among the people experiencing it.

Background: Trauma from adverse childhood experiences (ACEs) and serious traumatic events in adulthood is a significantly prevalent concern for public-health-hearing healthcare professionals. The pediatric and geriatric populations that audiologists often work with have been shown to be at an increased risk of experiencing traumatic events. Childhood and adult trauma can significantly impact the hearing and vestibular testing and treatment of these patients., Methods: This narrative review article discusses trauma-informed care (TIC) strategies that audiologists can use to recognize and respond to trauma in patients and prevent retraumatizing patients during their encounters in audiology clinics., Conclusions: This article will provide an overview of TIC and direct the reader to resources for their continued learning. Practical guidance on implementing trauma-informed practices in clinical audiology are also provided.

Purpose: More than 7% of the U.S. population identifies as LGBTQ+ (lesbian, gay, bisexual, transgender, queer, and other identities), meaning clinical audiologists in all settings are likely to encounter LGBTQ+ patients seeking audiological services. This conceptual clinical focus article (a) introduces contemporary LGBTQ+ terms, definitions, and pertinent issues; (b) summarizes the current state of knowledge on barriers to equitable hearing health care access and utilization for people who identify as LGBTQ+; (c) explores the legal, ethical, and moral obligations for audiologists to provide equitable care to people who identify as LGBTQ+; and (d) provides resources to continue to learn about salient LGBTQ+ issues., Conclusions: This clinical focus article provides actionable guidance to clinical audiologists on providing inclusive equitable care to LGBTQ+ patients. Practical actionable guidance on how clinical audiologists can make their clinical practice more inclusive for their patients who identify as LGBTQ+ is provided.

Purpose: Transgender people have been increasingly visible in society. Recent research has indicated that millions of Americans, 0.7% of the total population, identify as transgender. Although transgender people experience all the same auditory and vestibular disorders as people who are not transgender, there is a dearth of information about transgender issues in audiology graduate education and continuing education. The author discusses their positionality as a transgender audiologist and provides guidance on working with transgender patients from their experience and from the published literature., Conclusion: This tutorial provides an overview of transgender identity for clinical audiologists and summarizes the social, legal, and medical landscape of transgender identity as it relates to audiology.

Background: . An increasing number of people who are neurodiverse (people who have conditions such as autism, ADHD, and dyslexia) are pursuing higher education, including education and employment in the field of audiology METHODS: . This conceptual article was written by neurodivergent professionals to promote a cultural shift of inclusion for students, clinicians, researchers, and professors who identify as neurodivergent., Findings: . People with these conditions thrive with supportive accommodations in higher education and workplaces but little has been reported in the literature on neurodiversity accommodations in audiology education and practice CONCLUSIONS: . This article reviews the current literature on neurodiversity as it relates to audiology and discusses the practical and ethical considerations for neurodiversity inclusivity in the discipline of audiology., Competing Interests: Declaration of Competing Interest The authors have no significant financial or other competing interests to declare., (Copyright © 2022. Published by Elsevier GmbH.)

There are more transgender and gender-diverse clinical audiologists working today than might at first be apparent. The field of audiology, however, has unique interpersonal and structural factors that cause transgender audiologists to experience significant prejudice and discrimination from their patients and colleagues. Transgender audiologists who experience discrimination are at higher risk of stress, burnout, and leaving the field of audiology altogether. Improved education for healthcare professionals on LGBTQIA+ topics in graduate and continuing education may resolve many of the unequitable experiences that transgender audiologists experience and lead to improved patient care for our gender diverse patients., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Paucity of RCTs of non-drug technologies lead to widespread dependence on non-randomized studies. Relationship between nonrandomized study design attributes and biased estimates of treatment effects are poorly understood. Our purpose was to estimate the bias associated with specific nonrandomized study attributes among studies comparing transcatheter aortic valve implantation with surgical aortic valve replacement for the treatment of severe aortic stenosis., Results: We included 6 RCTs and 87 nonrandomized studies. Surgical risk scores were similar for comparison groups in RCTs, but were higher for patients having transcatheter aortic valve implantation in nonrandomized studies. Nonrandomized studies underestimated the benefit of transcatheter aortic valve implantation compared with RCTs. For example, nonrandomized studies without adjustment estimated a higher risk of postoperative mortality for transcatheter aortic valve implantation compared with surgical aortic valve replacement (OR 1.43 [95% CI 1.26 to 1.62]) than high quality RCTs (OR 0.78 [95% CI 0.54 to 1.11). Nonrandomized studies using propensity score matching (OR 1.13 [95% CI 0.85 to 1.52]) and regression modelling (OR 0.68 [95% CI 0.57 to 0.81]) to adjust results estimated treatment effects closer to high quality RCTs. Nonrandomized studies describing losses to follow-up estimated treatment effects that were significantly closer to high quality RCT than nonrandomized studies that did not., Conclusion: Studies with different attributes produce different estimates of treatment effects. Study design attributes related to the completeness of follow-up may explain biased treatment estimates in nonrandomized studies, as in the case of aortic valve replacement where high-risk patients were preferentially selected for the newer (transcatheter) procedure.

Heterozgyous spondyloepiphyseal dysplasia congenita (sedc/+) mice expressing a missense mutation in col2a1 exhibit a normal skeletal morphology but early-onset osteoarthritis (OA). We have recently examined knee articular cartilage obtained from homozygous (sedc/sedc) mice, which express a Stickler-like phenotype including dwarfism. We examined sedc/sedc mice at various levels to better understand the mechanistic process resulting in OA. Mutant sedc/sedc, and control (+/+) cartilages were compared at two, six and nine months of age. Tissues were fixed, decalcified, processed to paraffin sections, and stained with hematoxylin/eosin and safranin O/fast green. Samples were analyzed under the light microscope and the modified Mankin and OARSI scoring system was used to quantify the OA-like changes. Knees were stained with 1C10 antibody to detect the presence and distribution of type II collagen. Electron microscopy was used to study chondrocyte morphology and collagen fibril diameter. Compared with controls, mutant articular cartilage displayed decreased fibril diameter concomitant with increases in size of the pericellular space, Mankin and OARSI scores, cartilage thickness, chondrocyte clustering, proteoglycan staining and horizontal fissuring. In conclusion, homozygous sedc mice are subject to early-onset knee OA. We conclude that collagen in the mutant's articular cartilage (both heterozygote and homozygote) fails to provide the normal meshwork required for matrix integrity and overall cartilage stability.