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ImportanceSARS-CoV-2 infection can result in ongoing, relapsing, or new symptoms or other health effects after the acute phase of infection; termed post-acute sequelae of SARS-CoV-2 infection (PASC), or long COVID. The characteristics, prevalence, trajectory and mechanisms of PASC are ill-defined. The objectives of the Researching COVID to Enhance Recovery (RECOVER) Multi-site Observational Study of PASC in Adults (RECOVER-Adult) are to: (1) characterize PASC prevalence; (2) characterize the symptoms, organ dysfunction, natural history, and distinct phenotypes of PASC; (3) identify demographic, social and clinical risk factors for PASC onset and recovery; and (4) define the biological mechanisms underlying PASC pathogenesis.MethodsRECOVER-Adult is a combined prospective/retrospective cohort currently planned to enroll 14,880 adults aged ≥18 years. Eligible participants either must meet WHO criteria for suspected, probable, or confirmed infection; or must have evidence of no prior infection. Recruitment occurs at 86 sites in 33 U.S. states, Washington, DC and Puerto Rico, via facility- and community-based outreach. Participants complete quarterly questionnaires about symptoms, social determinants, vaccination status, and interim SARS-CoV-2 infections. In addition, participants contribute biospecimens and undergo physical and laboratory examinations at approximately 0, 90 and 180 days from infection or negative test date, and yearly thereafter. Some participants undergo additional testing based on specific criteria or random sampling. Patient representatives provide input on all study processes. The primary study outcome is onset of PASC, measured by signs and symptoms. A paradigm for identifying PASC cases will be defined and updated using supervised and unsupervised learning approaches with cross-validation. Logistic regression and proportional hazards regression will be conducted to investigate associations between risk factors, onset, and resolution of PASC symptoms.DiscussionRECOVER-Adult is the first national, prospective, longitudinal cohort of PASC among US adults. Results of this study are intended to inform public health, spur clinical trials, and expand treatment options.RegistrationNCT05172024.

Neisseria commensals are an indisputable source of resistance for their pathogenic relatives. However, the evolutionary paths commensal species take to reduced susceptibility in this genus have been relatively underexplored. Here, we leverage in vitro selection as a powerful screen to identify the genetic adaptations that produce azithromycin resistance (≥ 2 μg/mL) in the Neisseria commensal, N. elongata. Across multiple lineages (n = 7/16), we find mutations that reduce susceptibility to azithromycin converge on the locus encoding the 50S ribosomal L34 protein (rpmH) and the intergenic region proximal to the 30S ribosomal S3 protein (rpsC) through short tandem duplication events. Interestingly, one of the laboratory evolved mutations in rpmH is identical (7LKRTYQ12), and two nearly identical, to those recently reported to contribute to high-level azithromycin resistance in N. gonorrhoeae. Transformations into the ancestral N. elongata lineage confirmed the causality of both rpmH and rpsC mutations. Though most lineages inheriting duplications suffered in vitro fitness costs, one variant showed no growth defect, suggesting the possibility that it may be sustained in natural populations. Ultimately, studies like this will be critical for predicting commensal alleles that could rapidly disseminate into pathogen populations via allelic exchange across recombinogenic microbial genera.

The purpose of this study was to examine sex-specific differences in the blood glucose (BG) response to recurrent aerobic exercise in type 1 diabetes rats. Specifically, we examined the role of peak estrogen (E2) concentrations during proestrus on BG response to prolonged repetitive aerobic exercise. To do so, nineteen Sprague-Dawley rats were assigned to four exercised groups: control female (CXF; n = 5), control male (CXM; n = 5), diabetic female (DXF, n = 5) and diabetic male (DXM, n = 4). Diabetes was induced in DX groups via subcutaneous multiple injections of low dose streptozotocin (20mg/day for 7 days). After four days of exercise, muscle and liver glycogen content, liver gluconeogenic enzyme content, muscle Beta oxidation activity and BG responses to exercise were compared. The final bout of exercise took place during proestrus when E2 concentrations were at their highest in the female rats. During days 1–3 DXM had significantly lower BG concentrations during exercise than DXF. While both T1DM and non-T1DM females demonstrated higher hepatic G6Pase expression and muscle beta oxidation activity levels on day 4 exercise, no differences in BG response between the male and female T1DM rats were evident. Further, no differences in liver and muscle glycogen content following day 4 of exercise were seen between the sexes. These results would suggest that heightened E2 levels during proestrus may not be an important factor governing glucose counter regulatory response to exercise in female T1DM rats. Rather, the pre-exercise blood glucose levels are likely to be a large determinant of the blood glucose response to exercise in both male and female rats.

In this study, we use an exceptional skeleton of the pachycephalosaur Stegoceras validum (UALVP 2) to inform a comprehensive appendicular muscle reconstruction of the animal, with the goal of better understanding the functional morphology of the pachycephalosaur postcranial skeleton. We find that S. validum possessed a conservative forelimb musculature, particularly in comparison to early saurischian bipeds. By contrast, the pelvic and hind limb musculature are more derived, reflecting peculiarities of the underlying skeletal anatomy. The iliotibialis, ischiocaudalis, and caudofemoralis muscles have enlarged attachment sites and the caudofemoralis has greater leverage owing to the distal displacement of the fourth trochanter along the femur. These larger muscles, in combination with the wide pelvis and stout hind limbs, produced a stronger, more stable pelvic structure that would have proved advantageous during hypothesized intraspecific head-butting contests. The pelvis may have been further stabilized by enlarged sacroiliac ligaments, which stemmed from the unique medial iliac flange of the pachycephalosaurs. Although the pubis of UALVP 2 is not preserved, the pubes of other pachycephalosaurs are highly reduced. The puboischiofemoralis musculature was likely also reduced accordingly, and compensated for by the aforementioned improved pelvic musculature.

Waiting times for organs in the United States are long and vary widely across regions. Donor registration can increase the number of potential donors, but its effect on the actual number of organ transplants depends upon several factors. First among these factors is that deceased donor organ donation requires both that death occur in a way making recovery possible and that authorization to recover organs is obtained. We estimate the potential donor death rate and donor authorization rate conditional on potential donor death by donor registration status for each state and for key demographic groups. With this information, we then develop a simple measure of the value of a new donor registration. This combined measure using information on donor authorization rates and potential death rates varies widely across states and groups, suggesting that focusing registration efforts on high-value groups and locations can significantly increase the overall number of donors. Targeting high-value states raises 26.7 percent more donors than a uniform, nationwide registration effort. Our estimates can also be used to assess alternative, but complementary, policies such as protocols to improve authorization rates for non-registered potential donors.

The cranial anatomy of the flat-skulled hadrosaurine Edmontosaurus regalis (Ornithischia: Hadrosauridae) is extensively described here, based on the holotype and paratype collected from the middle part of the Horseshoe Canyon Formation in southern Alberta. Focus is given to previously undocumented features of ontogenetic and phylogenetic importance. This description facilitates overall osteological comparisons between E. regalis and other hadrosaurids (especially E. annectens), and revises the diagnosis of E. regalis, to which a new autapomorphy (the dorsal half of the jugal anterior process bearing a sharp posterolateral projection into the orbit) is added. We consider the recently named Ugrunaaluk kuukpikensis from the upper Campanian/lower Maastrichtian of Alaska a nomen dubium, and conservatively regard the Alaskan material as belonging to Edmontosaurus sp.. A phylogenetic analysis of Hadrosauroidea using maximum parsimony further corroborates the sister-taxon relationship between E. regalis and E. annectens. In the strict consensus tree, Hadrosaurus foulkii occurs firmly within the clade comprising all non-lambeosaurine hadrosaurids, supporting the taxonomic scheme that divides Hadrosauridae into Hadrosaurinae and Lambeosaurinae. Within Edmontosaurini, Kerberosaurus is posited as the sister taxon to the clade of Shantungosaurus + Edmontosaurus. The biogeographic reconstruction of Hadrosaurinae in light of the time-calibrated cladogram and probability calculation of ancestral areas for all internal nodes reveals a significantly high probability for the North American origin of the clade. However, the Laramidia-Appalachia dispersals around the Santonian-Campanian boundary, inferred from the biogeographic scenario for the North American origin of Hadrosaurinae, are in conflict with currently accepted paleogeographic models. By contrast, the Asian origin of Hadrosaurinae with its relatively low probability resulting from the biogeographic analysis is worth seriously considering, despite the lack of fossil material from the Santonian and lower Campanian of Asia. Extra fossil collecting in appropriate geographic locations and stratigraphic intervals of Asia and Europe will help to clarify the biogeographic dynamics of hadrosaurine dinosaurs in the near future.

SAP (SH2D1A) is required intrinsically in CD4 T cells to generate germinal center responses and long-term humoral immunity. SAP binds to SLAM family receptors, including SLAM, CD84, and Ly108 to enhance cytokine secretion and sustained T cell:B cell adhesion, which both improve T follicular helper (Tfh) cell aid to germinal center (GC) B cells. To understand the overlapping roles of multiple SLAM family receptors in germinal center responses, Slamf1Δ/Δ Slamf5Δ/Δ Slamf6Δ/Δ triple gene disruption (Slamf1,5,6Δ/Δ) mice were generated using CRISPR-Cas9 gene editing to eliminate expression of SLAM (CD150), CD84, and Ly108, respectively. Gene targeting was highly efficient, with 6 of 6 alleles disrupted in 14 of 23 pups and the majority of alleles disrupted in the remaining pups. NKT cell differentiation in Slamf1,5,6Δ/Δ mice was defective, but not completely absent. The remaining NKT cells exhibited substantially increased 2B4 (SLAMF4) expression. Surprisingly, there were no overt defects in germinal center responses to acute viral infections or protein immunizations in Slamf1,5,6Δ/Δ mice, unlike Sh2d1a-/- mice. Similarly, in the context of a competitive environment, SLAM family receptor expressing GC Tfh cell, GC B cell, and plasma cell responses exhibited no advantages over Slamf1,5,6Δ/Δ cells.

This study reports on a new ceratopsid, Spiclypeus shipporum gen et sp. nov., from the lower Coal Ridge Member of the Judith River Formation in Montana, USA, which dates to ~76 Ma (upper Campanian). The species is distinguished by rugose dorsal contacts on the premaxillae for the nasals, laterally projecting postorbital horncores, fully fused and anteriorly curled P1 and P2 epiparietals, and a posterodorsally projecting P3 epiparietal. The holotype specimen is also notable for its pathological left squamosal and humerus, which show varied signs of osteomyelitis and osteoarthritis. Although the postorbital horncores of Spiclypeus closely resemble those of the contemporaneous 'Ceratops', the horncores of both genera are nevertheless indistinguishable from those of some other horned dinosaurs, including Albertaceratops and Kosmoceratops; 'Ceratops' is therefore maintained as a nomen dubium. Cladistic analysis recovers Spiclypeus as the sister taxon to the clade Vagaceratops + Kosmoceratops, and appears transitional in the morphology of its epiparietals. The discovery of Spiclypeus adds to the poorly known dinosaur fauna of the Judith River Formation, and suggests faunal turnover within the formation.

Megaherbivorous dinosaurs were exceptionally diverse on the Late Cretaceous island continent of Laramidia, and a growing body of evidence suggests that this diversity was facilitated by dietary niche partitioning. We test this hypothesis using the fossil megaherbivore assemblage from the Dinosaur Park Formation (upper Campanian) of Alberta as a model. Comparative tooth morphology and wear, including the first use of quantitative dental microwear analysis in the context of Cretaceous palaeosynecology, are used to infer the mechanical properties of the foods these dinosaurs consumed. The phylliform teeth of ankylosaurs were poorly adapted for habitually processing high-fibre plant matter. Nevertheless, ankylosaur diets were likely more varied than traditionally assumed: the relatively large, bladed teeth of nodosaurids would have been better adapted to processing a tougher, more fibrous diet than the smaller, cusp-like teeth of ankylosaurids. Ankylosaur microwear is characterized by a preponderance of pits and scratches, akin to modern mixed feeders, but offers no support for interspecific dietary differences. The shearing tooth batteries of ceratopsids are much better adapted to high-fibre herbivory, attested by their scratch-dominated microwear signature. There is tentative microwear evidence to suggest differences in the feeding habits of centrosaurines and chasmosaurines, but statistical support is not significant. The tooth batteries of hadrosaurids were capable of both shearing and crushing functions, suggestive of a broad dietary range. Their microwear signal overlaps broadly with that of ankylosaurs, and suggests possible dietary differences between hadrosaurines and lambeosaurines. Tooth wear evidence further indicates that all forms considered here exhibited some degree of masticatory propaliny. Our findings reveal that tooth morphology and wear exhibit different, but complimentary, dietary signals that combine to support the hypothesis of dietary niche partitioning. The inferred mechanical and dietary patterns appear constant over the 1.5 Myr timespan of the Dinosaur Park Formation megaherbivore chronofauna, despite continual species turnover.

Pathogenic Gram-negative bacteria use type III secretion (T3S) to inject effector proteins into the host cell to create appropriate conditions for infection and intracellular replication. Chlamydia spp. are believed to use T3S to infect their host cell, and the translocator proteins are an essential component of this system. Chlamydia pneumoniae contains genes encoding two sets of translocator proteins; CopB and CopD, and CopB2 and CopD2. In this study, we identified novel interactions between CopD and three type III secretion proteins; namely, CopN, CdsN, and CdsF. We identified a CopD putative chaperone binding motif, PxLxxP, within the N-terminal region (CopD amino acids 120-125), which was necessary for interaction with its putative chaperone LcrH_1. Using size exclusion chromatography, we showed that CopD and LcrH_1 formed higher order structures in solution with CopD and LcrH_1 binding in a ratio of 1∶1, which is unique for T3SS translocator proteins. Lastly, we showed that antibodies to CopD reduced C. pneumoniae infectivity by >95%. Collectively, this data suggests that CopD plays a critical role in pathogenesis and likely functions as a hydrophobic translocator of the type III secretion system in Chlamydia pneumoniae.

Megaherbivorous dinosaur coexistence on the Late Cretaceous island continent of Laramidia has long puzzled researchers, owing to the mystery of how so many large herbivores (6-8 sympatric species, in many instances) could coexist on such a small (4-7 million km(2)) landmass. Various explanations have been put forth, one of which-dietary niche partitioning-forms the focus of this study. Here, we apply traditional morphometric methods to the skulls of megaherbivorous dinosaurs from the Dinosaur Park Formation (upper Campanian) of Alberta to infer the ecomorphology of these animals and to test the niche partitioning hypothesis. We find evidence for niche partitioning not only among contemporaneous ankylosaurs, ceratopsids, and hadrosaurids, but also within these clades at the family and subfamily levels. Consubfamilial ceratopsids and hadrosaurids differ insignificantly in their inferred ecomorphologies, which may explain why they rarely overlap stratigraphically: interspecific competition prevented their coexistence.

SAP (SH2D1A) is required intrinsically in CD4 T cells to generate germinal center responses and long-term humoral immunity. SAP binds to SLAM family receptors, including SLAM, CD84, and Ly108 to enhance cytokine secretion and sustained T cell:B cell adhesion, which both improve T follicular helper (Tfh) cell aid to germinal center (GC) B cells. To understand the overlapping roles of multiple SLAM family receptors in germinal center responses, Slamf1Δ/Δ Slamf5Δ/Δ Slamf6Δ/Δ triple gene disruption (Slamf1,5,6Δ/Δ) mice were generated using CRISPR-Cas9 gene editing to eliminate expression of SLAM (CD150), CD84, and Ly108, respectively. Gene targeting was highly efficient, with 6 of 6 alleles disrupted in 14 of 23 pups and the majority of alleles disrupted in the remaining pups. NKT cell differentiation in Slamf1,5,6Δ/Δ mice was defective, but not completely absent. The remaining NKT cells exhibited substantially increased 2B4 (SLAMF4) expression. Surprisingly, there were no overt defects in germinal center responses to acute viral infections or protein immunizations in Slamf1,5,6Δ/Δ mice, unlike Sh2d1a-/- mice. Similarly, in the context of a competitive environment, SLAM family receptor expressing GC Tfh cell, GC B cell, and plasma cell responses exhibited no advantages over Slamf1,5,6Δ/Δ cells. [ABSTRACT FROM AUTHOR]

Pathogenic Gram-negative bacteria use type III secretion (T3S) to inject effector proteins into the host cell to create appropriate conditions for infection and intracellular replication. Chlamydia spp. are believed to use T3S to infect their host cell, and the translocator proteins are an essential component of this system. Chlamydia pneumoniae contains genes encoding two sets of translocator proteins; CopB and CopD, and CopB2 and CopD2. In this study, we identified novel interactions between CopD and three type III secretion proteins; namely, CopN, CdsN, and CdsF. We identified a CopD putative chaperone binding motif, PxLxxP, within the N-terminal region (CopD amino acids 120–125), which was necessary for interaction with its putative chaperone LcrH_1. Using size exclusion chromatography, we showed that CopD and LcrH_1 formed higher order structures in solution with CopD and LcrH_1 binding in a ratio of 1∶1, which is unique for T3SS translocator proteins. Lastly, we showed that antibodies to CopD reduced C. pneumoniae infectivity by >95%. Collectively, this data suggests that CopD plays a critical role in pathogenesis and likely functions as a hydrophobic translocator of the type III secretion system in Chlamydia pneumoniae. [ABSTRACT FROM AUTHOR]

Stable isotope data have made pivotal contributions to nearly every discipline of the physical and natural sciences. As the generation and application of stable isotope data continues to grow exponentially, so does the need for a unifying data repository to improve accessibility and promote collaborative engagement. This paper provides an overview of the design, development, and implementation of IsoBank (www.isobank.org), a community-driven initiative to create an open-access repository for stable isotope data implemented online in 2021. A central goal of IsoBank is to provide a web-accessible database supporting interdisciplinary stable isotope research and educational opportunities. To achieve this goal, we convened a multi-disciplinary group of over 40 analytical experts, stable isotope researchers, database managers, and web developers to collaboratively design the database. This paper outlines the main features of IsoBank and provides a focused description of the core metadata structure. We present plans for future database and tool development and engagement across the scientific community. These efforts will help facilitate interdisciplinary collaboration among the many users of stable isotopic data while also offering useful data resources and standardization of metadata reporting across eco-geoinformatics landscapes., Competing Interests: The authors declare no competing interests., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Importance: The prevalence, pathophysiology, and long-term outcomes of COVID-19 (post-acute sequelae of SARS-CoV-2 [PASC] or "Long COVID") in children and young adults remain unknown. Studies must address the urgent need to define PASC, its mechanisms, and potential treatment targets in children and young adults., Observations: We describe the protocol for the Pediatric Observational Cohort Study of the NIH's REsearching COVID to Enhance Recovery (RECOVER) Initiative. RECOVER-Pediatrics is an observational meta-cohort study of caregiver-child pairs (birth through 17 years) and young adults (18 through 25 years), recruited from more than 100 sites across the US. This report focuses on two of four cohorts that comprise RECOVER-Pediatrics: 1) a de novo RECOVER prospective cohort of children and young adults with and without previous or current infection; and 2) an extant cohort derived from the Adolescent Brain Cognitive Development (ABCD) study (n = 10,000). The de novo cohort incorporates three tiers of data collection: 1) remote baseline assessments (Tier 1, n = 6000); 2) longitudinal follow-up for up to 4 years (Tier 2, n = 6000); and 3) a subset of participants, primarily the most severely affected by PASC, who will undergo deep phenotyping to explore PASC pathophysiology (Tier 3, n = 600). Youth enrolled in the ABCD study participate in Tier 1. The pediatric protocol was developed as a collaborative partnership of investigators, patients, researchers, clinicians, community partners, and federal partners, intentionally promoting inclusivity and diversity. The protocol is adaptive to facilitate responses to emerging science., Conclusions and Relevance: RECOVER-Pediatrics seeks to characterize the clinical course, underlying mechanisms, and long-term effects of PASC from birth through 25 years old. RECOVER-Pediatrics is designed to elucidate the epidemiology, four-year clinical course, and sociodemographic correlates of pediatric PASC. The data and biosamples will allow examination of mechanistic hypotheses and biomarkers, thus providing insights into potential therapeutic interventions., Clinical Trials.gov Identifier: Clinical Trial Registration: http://www.clinicaltrials.gov. Unique identifier: NCT05172011., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: Brett Anderson reported receiving direct support for work not related to RECOVER work/publications from Genentech and the National Institute of Allergy and Immunology. Walter Dehority reported receiving grant support from Merck and participating in research for the Moderna COVID-19 pediatric vaccine trial and the Pfizer Paxlovid trial. Alex Fiks reported receiving support from NJM insurance and personal consulting fees not related to this paper from Rutgers University and the American Academy of Pediatrics. Ashraf Harahsheh reported serving as a scientific advisory board member unrelated to this paper for OP2 DRUGS. Lawrence Kleinman reported serving as an unpaid member of the Board of Directors for the DARTNet Institute, as a principle investigator at Quality Matters, Inc., and as the Vice Chair for the Borough of Metuchen Board of Health. Dr. Kleinman also reported grant support for work not related to RECOVER work/publications from NIH, HRSA, and the Robert Wood Johnson Foundation. Dr. Kleinman also reported minority individual stock ownership in Apple Computer, Sanofi SA, Experion, GlaxoSmithKline, Magyar Bank, Regeneron Pharmaceuticals, JP Morgan Chase, and Amgen Inc. Torri Metz reported participating as a Principle Investigator in the medical advisory board for the planning of a Pfizer clinical trial of SARS-CoV-2 vaccination in pregnancy. She is also a principle investigator for a Pfizer study evaluating the pharmacokinetics of Paxlovid in pregnant people with COVID-19. Joshua Milner reported serving as a member of the Scientific Advisory Board for Blueprint Medicines, in a capacity unrelated to RECOVER work/publications. This does not alter our adherence to PLOS ONE policies on sharing data and materials., (Copyright: © 2024 Gross et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The primeval function of the mammalian hippocampus (HPC) remains uncertain. Implicated in learning and memory, spatial navigation, and neuropsychological disorders, evolutionary theory suggests that the HPC evolved from a primeval chemosensory epithelium. Deficits in sensing of internal body status ('interoception') in patients with HPC lesions argue that internal sensing may be conserved in higher vertebrates. We studied the expression patterns in mouse brain of 250 endocrine receptors that respond to blood-borne ligands. Key findings are (i) the proportions and levels of endocrine receptor expression in the HPC are significantly higher than in all other comparable brain regions. (ii) Surprisingly, the distribution of endocrine receptor expression within mouse HPC was found to be highly structured: receptors signaling 'challenge' are segregated in dentate gyrus (DG), whereas those signaling 'sufficiency' are principally found in cornu ammonis (CA) regions. Selective expression of endocrine receptors in the HPC argues that interoception remains a core feature of hippocampal function. Further, we report that ligands of DG receptors predominantly inhibit both synaptic potentiation and neurogenesis, whereas CA receptor ligands conversely promote both synaptic potentiation and neurogenesis. These findings suggest that the hippocampus acts as an integrator of body status, extending its role in context-dependent memory encoding from 'where' and 'when' to 'how I feel'. Implications for anxiety and depression are discussed., Competing Interests: The authors have declared that no competing interests exist.