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Abstract Histone H3-mutant gliomas are deadly brain tumors characterized by a dysregulated epigenome and stalled differentiation. In contrast to the extensive datasets available on tumor cells, limited information exists on their tumor microenvironment (TME), particularly the immune infiltrate. Here, we characterize the immune TME of H3.3K27M and G34R/V-mutant gliomas, and multiple H3.3K27M mouse models, using transcriptomic, proteomic and spatial single-cell approaches. Resolution of immune lineages indicates high infiltration of H3-mutant gliomas with diverse myeloid populations, high-level expression of immune checkpoint markers, and scarce lymphoid cells, findings uniformly reproduced in all H3.3K27M mouse models tested. We show these myeloid populations communicate with H3-mutant cells, mediating immunosuppression and sustaining tumor formation and maintenance. Dual inhibition of myeloid cells and immune checkpoint pathways show significant therapeutic benefits in pre-clinical syngeneic mouse models. Our findings provide a valuable characterization of the TME of oncohistone-mutant gliomas, and insight into the means for modulating the myeloid infiltrate for the benefit of patients.

Abstract Glioblastoma is the most common and deadliest brain tumour in adults, with a median survival of 15 months under the current standard of care. Immunotherapies like immune checkpoint inhibitors and oncolytic viruses have been extensively studied to improve this endpoint. However, most thus far have failed. To improve the efficacy of immunotherapies to treat glioblastoma, new single-cell imaging modalities like imaging mass cytometry can be leveraged and integrated with computational models. This enables a better understanding of the tumour microenvironment and its role in treatment success or failure in this hard-to-treat tumour. Here, we implemented an agent-based model that allows for spatial predictions of combination chemotherapy, oncolytic virus, and immune checkpoint inhibitors against glioblastoma. We initialised our model with patient imaging mass cytometry data to predict patient-specific responses and found that oncolytic viruses drive combination treatment responses determined by intratumoral cell density. We found that tumours with higher tumour cell density responded better to treatment. When fixing the number of cancer cells, treatment efficacy was shown to be a function of CD4 + T cell and, to a lesser extent, of macrophage counts. Critically, our simulations show that care must be put into the integration of spatial data and agent-based models to effectively capture intratumoral dynamics. Together, this study emphasizes the use of predictive spatial modelling to better understand cancer immunotherapy treatment dynamics, while highlighting key factors to consider during model design and implementation.

ABSTRACT Understanding factors influencing the composition and maintenance of beneficial host-associated microbial communities is central to understanding their ecological, evolutionary, and health consequences for hosts. Host immunity is often implicated as a regulator of these microbiota, but immunity may also play a disruptive role, with responses to infection perturbing beneficial communities. Such effects may be more prominent from innate immune responses, with more rapid-acting and often non-specific components, compared to adaptive responses. We investigated how upregulation of antibacterial immunity in the bumble bee Bombus impatiens affects its core gut microbiota, testing the hypothesis that immunity-induced perturbation impacts the microbiota structure. Freshly emerged adult bees were fed a microbiota inoculum before receiving a non-pathogenic immune stimulation injection. We quantified microbial communities using 16S rRNA amplicon sequencing and targeted quantitative PCR. Coarse community membership shows apparent robustness, but we find that immune stimulation alters the abundance of two core community members, Gilliamella and Snodgrassella. Moreover, a positive association in communities between these bacteria is perturbed following a Gram-negative challenge. The observed changes in the gut microbial community are suggestive of immune response-induced dysbiosis, linking ecological interactions across levels between hosts, their pathogens, and their beneficial gut microbiota. The potential for collateral perturbation of the natural gut microbiota following an innate immune response may contribute to immune costs, shaping the evolutionary optimization of immune investment depending on the ecological context.IMPORTANCEOur work demonstrates how innate immunity may influence the host-associated microbiota. While previous work has demonstrated the role of adaptive immunity in regulating the microbiota, we show that stimulation of an innate immune response in bumble bees may disrupt the native gut microbial community by shifting individual abundances of some members and pairwise associations. This work builds upon previous work in bumble bees demonstrating factors determining microbe colonization of hosts and microbiota membership, implicating immune response-induced changes as a factor shaping these important gut communities. While some microbiota members appear unaffected, changes in others and the community overall suggests that collateral perturbation of the native gut microbiota upon an innate immune response may serve as an additional selective pressure that shapes the evolution of host innate immunity.

Ernest Moles,1– 4 David W Chang,1– 3 Friederike M Mansfeld,1– 3 Alastair Duly,1,2 Kathleen Kimpton,1 Amy Logan,1– 4 Christopher B Howard,5 Kristofer J Thurecht,5,6 Maria Kavallaris1– 4 1Children’s Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, NSW, 2052, Australia; 2UNSW Australian Centre for Nanomedicine, Faculty of Engineering, UNSW, Sydney, NSW, 2052, Australia; 3School of Clinical Medicine, Faculty of Medicine & Health, UNSW, Sydney, NSW, 2052, Australia; 4UNSW RNA Institute, Faculty of Science, UNSW, Sydney, NSW, 2052, Australia; 5Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St Lucia, QLD, 4072, Australia; 6Centre for Advanced Imaging, ARC Training Centre for Innovation in Biomedical Imaging Technologies, University of Queensland, St Lucia, QLD, 4072, AustraliaCorrespondence: Ernest Moles; Maria Kavallaris, Children’s Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, NSW, 2052, Australia, Email emoles@ccia.org.au; m.kavallaris@ccia.unsw.edu.auIntroduction: Despite improvements in chemotherapy and molecularly targeted therapies, the life expectancy of patients with advanced non-small cell lung cancer (NSCLC) remains less than 1 year. There is thus a major global need to advance new treatment strategies that are more effective for NSCLC. Drug delivery using liposomal particles has shown success at improving the biodistribution and bioavailability of chemotherapy. Nevertheless, liposomal drugs lack selectivity for the cancer cells and have a limited ability to penetrate the tumor site, which severely limits their therapeutic potential. Epidermal growth factor receptor (EGFR) is overexpressed in NSCLC tumors in about 80% of patients, thus representing a promising NSCLC-specific target for redirecting liposome-embedded chemotherapy to the tumor site.Methods: Herein, we investigated the targeting of PEGylated liposomal doxorubicin (Caelyx), a powerful off-the-shelf antitumoral liposomal drug, to EGFR as a therapeutic strategy to improve the specific delivery and intratumoral accumulation of chemotherapy in NSCLC. EGFR-targeting of Caelyx was enabled through its complexing with a polyethylene glycol (PEG)/EGFR bispecific antibody fragment. Tumor targeting and therapeutic potency of our treatment approach were investigated in vitro using a panel of NSCLC cell lines and 3D tumoroid models, and in vivo in a cell line-derived tumor xenograft model.Results: Combining Caelyx with our bispecific antibody generated uniform EGFR-targeted particles with improved binding and cytotoxic efficacy toward NSCLC cells. Effects were exclusive to cancer cells expressing EGFR, and increments in efficacy positively correlated with EGFR density on the cancer cell surface. The approach demonstrated increased penetration within 3D spheroids and was effective at targeting and suppressing the growth of NSCLC tumors in vivo while reducing drug delivery to the heart.Conclusion: EGFR targeting represents a successful approach to enhance the selectivity and therapeutic potency of liposomal chemotherapy toward NSCLC. Keywords: targeted drug delivery, bispecific antibodies, PEGylated liposomal doxorubicin, EGFR targeting, non-small cell lung cancer

Abstract Background Pain from osteoarthritis (OA) is one of the top causes of disability worldwide, but effective treatment is lacking. Nociceptive factors are released by activated synovial macrophages in OA, but depletion of synovial macrophages paradoxically worsens inflammation and tissue damage in previous studies. Rather than depleting macrophages, we hypothesized that inhibiting macrophage activation may improve pain without increasing tissue damage. We aimed to identify key mechanisms mediating synovial macrophage activation and test the role of STAT signaling in macrophages on pain outcomes in experimental knee OA. Methods We induced experimental knee OA in rats via knee destabilization surgery, and performed RNA sequencing analysis on sorted synovial tissue macrophages to identify macrophage activation mechanisms. Liposomes laden with STAT1 or STAT6 inhibitors, vehicle (control), or clodronate (depletion control) were delivered selectively to synovial macrophages via serial intra-articular injections up to 12 weeks after OA induction. Treatment effects on knee and hindpaw mechanical pain sensitivity were measured during OA development, along with synovitis, cartilage damage, and synovial macrophage infiltration using histopathology and immunofluorescence. Lastly, crosstalk between drug-treated synovial tissue and articular chondrocytes was assessed in co-culture. Results The majority of pathways identified by transcriptomic analyses in OA synovial macrophages involve STAT signaling. As expected, macrophage depletion reduced pain, but increased synovial tissue fibrosis and vascularization. In contrast, STAT6 inhibition in macrophages led to marked, sustained improvements in mechanical pain sensitivity and synovial inflammation without worsening synovial or cartilage pathology. During co-culture, STAT6 inhibitor-treated synovial tissue had minimal effects on healthy chondrocyte gene expression, whereas STAT1 inhibitor-treated synovium induced changes in numerous cartilage turnover-related genes. Conclusion These results suggest that STAT signaling is a major mediator of synovial macrophage activation in experimental knee OA. STAT6 may be a key mechanism mediating the release of nociceptive factors from macrophages and the development of mechanical pain sensitivity. Whereas therapeutic depletion of macrophages paradoxically increases inflammation and fibrosis, blocking STAT6-mediated synovial macrophage activation may be a novel strategy for OA-pain management without accelerating tissue damage.

Abstract Organic carbon (OC) sedimentation in marine sediments is the largest long‐term sink of atmospheric CO2 after silicate weathering. Understanding the mechanistic and quantitative aspects of OC delivery and preservation in marine sediments is critical for predicting the role of the oceans in modulating global climate. Yet, estimates of the global OC sedimentation in marginal settings span an order of magnitude, and the primary controls of OC preservation remain highly debated. Here, we provide the first global bottom‐up estimate of OC sedimentation along the margins using a synthesis of literature data. We quantify both terrestrial‐ and marine‐sourced OC fluxes and perform a statistical analysis to discern the key factors influencing their magnitude. We find that the margins host 23.2 ± 3.5 Tmol of OC sedimentation annually, with approximately 84% of marine origin. Accordingly, we calculate that only 2%–3% of OC exported from the euphotic zone escapes remineralization before sedimentation. Surprisingly, over half of all global OC sedimentation occurs below bottom waters with oxygen concentrations greater than 180 μM, while less than 4% occurs in settings with

Background: Bloodstream infections (BSIs) are an important cause of morbidity and mortality in severely ill patients, contributing to increased length of hospital stay and higher cost of care. Alberta Health Services Infection Prevention and Control (IPC) conducts inpatient surveillance of new episodes of BSIs with methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) or carbapenemase-producing organisms (CPO) in 112 acute care facilities. A case-finding process was undertaken to verify the accuracy of BSI data entry. Methods: All positive MRSA, VRE or CPO blood cultures in 2021 were linked to the Inpatient Discharge Abstract Database (DAD) and the National Ambulatory Care Reporting System (NACRS) to identify new cases during acute care admissions. The results were then compared to surveillance records captured by infection control professionals (ICPs). Cases with unmatched culture date and/or encounter date and cases not identified by ICPs were screened by the study team with final decision made by ICPs. Results were analyzed by ARO and by % increase in number of surveillance records. Results: The laboratory linkage identified 286 new cases. Comparing to surveillance records (n = 248) captured by ICPs, 137 (57.3%) had matching collection dates and encounter dates, 85 (35.6%) had close matches on collection dates and encounter dates, 17 (7.1%) records had either matching collection dates or encounter dates, and 1 (0.4%) record did not have any matches on dates. There were 46 records identified in the laboratory data that were not in the surveillance system and 8 records that were in the surveillance system but not matched to the laboratory data. After review, 22 Surveillance records had data entry errors (1 CPO BSI, 20 MRSA BSI, and 1 VRE BSI), and there were 14 BSI records found to be missing (13 MRSA BSI, 1 VRE BSI). This represents a 6% increase in MRSA BSI and a 3% increase in VRE BSI identified in 2021 and no increase in CPO BSI. Conclusions: A laboratory validation to determine if BSIs with an ARO were missed during routine IPC surveillance identified a small proportion of missed bloodstream infections. The most common reason for the miss was admission through the emergency department with multiple blood cultures collected during a single admission. These results will be shared with the Infection Control program to facilitate correct BSI capture.

BackgroundOverdose Fatality Review (OFR) is an important public health tool for shaping overdose prevention strategies in communities. However, OFR teams review only a few cases at a time, which typically represent a small fraction of the total fatalities in their jurisdiction. Such limited review could result in a partial understanding of local overdose patterns, leading to policy recommendations that do not fully address the broader community needs. ObjectiveThis study explored the potential to enhance conventional OFRs with a data dashboard, incorporating visualizations of touchpoints—events that precede overdoses—to highlight prevention opportunities. MethodsWe conducted 2 focus groups and a survey of OFR experts to characterize their information needs and design a real-time dashboard that tracks and measures decedents’ past interactions with services in Indiana. Experts (N=27) were engaged, yielding insights on essential data features to incorporate and providing feedback to guide the development of visualizations. ResultsThe findings highlighted the importance of showing decedents’ interactions with health services (emergency medical services) and the justice system (incarcerations). Emphasis was also placed on maintaining decedent anonymity, particularly in small communities, and the need for training OFR members in data interpretation. The developed dashboard summarizes key touchpoint metrics, including prevalence, interaction frequency, and time intervals between touchpoints and overdoses, with data viewable at the county and state levels. In an initial evaluation, the dashboard was well received for its comprehensive data coverage and its potential for enhancing OFR recommendations and case selection. ConclusionsThe Indiana touchpoints dashboard is the first to display real-time visualizations that link administrative and overdose mortality data across the state. This resource equips local health officials and OFRs with timely, quantitative, and spatiotemporal insights into overdose risk factors in their communities, facilitating data-driven interventions and policy changes. However, fully integrating the dashboard into OFR practices will likely require training teams in data interpretation and decision-making.

Coccoloba uvifera L. (seagrape) is a primarily dioecious neotropical tree species which often grows in the beach–forest transitional ecotone of coastal strand vegetation. We used five maternally inherited non-coding chloroplast regions to characterize the phytogeography of C. uvifera collected across the Caribbean Basin and Florida. Bayesian analysis revealed divergence between the Aruba–Trinidad–Tobago–Antigua–Jamaica island group and the continental Belize–Florida–US Virgin Islands (USVI) group at 1.78 million years before present (mybp), divergence between the Belize and Florida–USVI groups at 1.08 mybp, and a split of Antigua–Jamaica from Aruba–Trinidad–Tobago at 0.217 mybp. Haplotype network analysis supports the three clades, with the island group possessing the oldest haplotype. Based on geology and proximity, these clades correspond to South American (oldest), Central American, and North American (most recent). Coccoloba uvifera demographic expansion occurred during the Pleistocene epoch and peaked near the end of the last glacial maximum (ca. 0.026–0.019 mybp) when the global sea levels were 125 m lower than today. Our findings also reveal that tropical cyclones, which often impact coastal strand vegetation, did not affect genetic diversity. However, there was a positive association between latitude and the average number of substitutions, further enriching our understanding of the species’ phytogeography.

Increases in organic carbon within agricultural soils are widely recognized as a “negative emission” that removes CO2 from the atmosphere. Accurate quantification of soil organic carbon (SOC) to a certain depth in the spatial domain is critical for the effective implementation of improved land management practices in croplands. Currently, there is a lack of understanding regarding what depth strategy should be used to estimate SOC at 0–30 cm when sample datasets come from multiple depths. Furthermore, few studies have examined depth strategies for mapping SOC at the agricultural management level (i.e., field level), opting instead for point-based analysis. Here, three types of approaches with different depth strategies were evaluated for their ability to quantify 0–30 cm SOC content based on soil samples from 0–5 (surface), 5–30 (subsurface), and 0–30 cm (full column). These approaches involved the generalized additive model and machine learning techniques, i.e., artificial neural networks, random forest, and XGBoost. The soil samples used for the model evaluation and selection consisted of the newly collected samples in 2020–2022 and the Rapid Carbon Assessment (RaCA) legacy samples collected in 2010–2011. Environmental covariates corresponding to these SOC measurements were used in model training, including long-term physical climate, short-term weather, topographic and edaphic, and remotely sensed variables. Among the models evaluated in this study, the XGB regression model with a full column depth assignment strategy yielded the best prediction performance for 0–30 cm SOC content, with an r2 (squared Pearson correlation coefficient) of 0.48, an RMSE (root mean square error) of 0.29%, an ME (mean error) of 0.06%, an MAE of 0.25%, and an MEC (modeling efficiency coefficient) of 0.36 at the pixel level and an r2 of 0.64, an RMSE of 0.32%, an ME of −0.20%, an MAE of 0.28%, and an MEC of 0.48 at the field level. This study highlights that machine learning models with a full column depth strategy should be used to quantify 0–30 cm SOC content in agricultural soils over the continental United States (CONUS).

Abstract Collectively, the MYC family of oncoprotein transcription factors is overexpressed in more than half of all malignancies. The ability of MYC proteins to access chromatin is fundamental to their role in promoting oncogenic gene expression programs in cancer and this function depends on MYC–cofactor interactions. One such cofactor is the chromatin regulator WDR5, which in models of Burkitt lymphoma facilitates recruitment of the c-MYC protein to chromatin at genes associated with protein synthesis, allowing for tumor progression and maintenance. However, beyond Burkitt lymphoma, it is unknown whether these observations extend to other cancers or MYC family members, and whether WDR5 can be deemed as a “universal” MYC recruiter. Here, we focus on N-MYC amplified neuroblastoma to determine the extent of colocalization between N-MYC and WDR5 on chromatin while also demonstrating that like c-MYC, WDR5 can facilitate the recruitment of N-MYC to conserved WDR5-bound genes. We conclude based on this analysis that N-MYC and WDR5 colocalize invariantly across cell lines at predicted sites of facilitated recruitment associated with protein synthesis genes. Surprisingly, we also identify N-MYC-WDR5 cobound genes that are associated with DNA repair and cell cycle processes. Dissection of chromatin binding characteristics for N-MYC and WDR5 at all cobound genes reveals that sites of facilitated recruitment are inherently different than most N-MYC-WDR5 cobound sites. Our data reveals that WDR5 acts as a universal MYC recruiter at a small cohort of previously identified genes and highlights novel biological functions that may be coregulated by N-MYC and WDR5 to sustain the neuroblastoma state.

Terri Call,1,* Andrew D Pucker,1,* Gerald McGwin Jr,2 Quentin X Franklin,1 Amy Logan1 1Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, USA; 2Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA*These authors contributed equally to this workCorrespondence: Andrew D Pucker, University of Alabama at Birmingham, School of Optometry, 1716 University Blvd, Birmingham, AL, 35233, USA, Tel +1 920 579-2900, Email andrewpucker@hotmail.comPurpose: To map contact lens (CL) comfort over the full wear day and across 1 month’s wear in established, asymptomatic to minimally symptomatic, reusable, soft CL wearers.Methods: Adult, 18- to 45-year-old, participants were recruited and required to have 20/20 best-corrected visual acuity or better and must have been asymptomatic to minimally symptomatic CL wearers. Participants were required to be able to wear TOTAL30® sphere CLs and have minimal astigmatism. Participants were fit in the study CLs and asked to wear these CLs daily for the next month for 16 hours per day each day. Participants were asked to complete a visual analog scale (VAS) survey via text message at time of CL application and after 8, 10, 12, 14, and 16 hours of wear and at CL removal on days 1, 2, 3, 4, and 5 and at 2 weeks and 1 month. The utilized VAS had a ± 50 scale with positive scores being comfortable, negative scores being uncomfortable, and scores of 0 being neutral comfort.Results: Forty-eight participants were recruited who had a mean ± SD age of 26.2 ± 5.2 years (71% female). Mean initial VAS CL comfort scores at initial CL dispense were 45.56 ± 9.20 units. Mean CL wear times for any of the days evaluated were at least 14.80 ± 2.41 hours per day and did not differ across the study (p = 0.77). Mean comfort VAS scores significantly decreased over the wear day (all days p ≤ 0.02), yet there were no significant differences in VAS comfort scores across the same time of day for the duration of the study (all times p ≥ 0.06).Conclusion: This study determined that while CL wearers were slightly less comfortable at the end of the day compared to application, this comfort change was minimal given that the average participants had overwhelmingly good comfort at all time-points evaluated. Comfort scores were likewise consistent across 1 month of wear.Keywords: comfort, contact lenses, monthly, reusable, text message, visual analog scale

AbstractUnderstanding statistics is essential for engineers. However, statistics courses remain challenging for many students, as they find them rigid, abstract, and demanding. Prior research has indicated that using project-based learning (PjBL) to demonstrate the relevance of statistics to students can have a significant effect on learning in these courses. Consequently, this study sought to explore the impact of a PjBL intervention on student perceptions of the relevance of engineering and statistics. The purpose of the intervention was to help students understand the connection between statistics and their academic majors, lives, and future careers. Four mini-projects connecting statistics to students’ experiences and future careers were designed and implemented during a 16-week course and students’ perceptions were compared to those of students who took a traditional statistics course. Students enrolled in the experimental group (a synchronous learning experience) and the control group (an online learning experience) were sent the same survey at the end of the semester. The survey results suggest that the PjBL intervention could potentially increase students’ understanding of the usefulness of statistics and effectively enhance their perceptions of belonging to the engineering community. This study summarizes the results of this PjBL intervention, the limitations of the research design, and suggests implications for improving future statistics courses in the context of engineering.

Abstract Background Risk factors for nosocomial COVID-19 outbreaks continue to evolve. The aim of this study was to investigate a multi-ward nosocomial outbreak of COVID-19 between 1st September and 15th November 2020, occurring in a setting without vaccination for any healthcare workers or patients. Methods Outbreak report and retrospective, matched case–control study using incidence density sampling in three cardiac wards in an 1100-bed tertiary teaching hospital in Calgary, Alberta, Canada. Patients were confirmed/probable COVID-19 cases and contemporaneous control patients without COVID-19. COVID-19 outbreak definitions were based on Public Health guidelines. Clinical and environmental specimens were tested by RT-PCR and as applicable quantitative viral cultures and whole genome sequencing were conducted. Controls were inpatients on the cardiac wards during the study period confirmed to be without COVID-19, matched to outbreak cases by time of symptom onset dates, age within ± 15 years and were admitted in hospital for at least 2 days. Demographics, Braden Score, baseline medications, laboratory measures, co-morbidities, and hospitalization characteristics were collected on cases and controls. Univariate and multivariate conditional logistical regression was used to identify independent risk factors for nosocomial COVID-19. Results The outbreak involved 42 healthcare workers and 39 patients. The strongest independent risk factor for nosocomial COVID-19 (IRR 3.21, 95% CI 1.47–7.02) was exposure in a multi-bedded room. Of 45 strains successfully sequenced, 44 (97.8%) were B.1.128 and differed from the most common circulating community lineages. SARS-CoV-2 positive cultures were detected in 56.7% (34/60) of clinical and environmental specimens. The multidisciplinary outbreak team observed eleven contributing events to transmission during the outbreak. Conclusions Transmission routes of SARS-CoV-2 in hospital outbreaks are complex; however multi-bedded rooms play a significant role in the transmission of SARS-CoV-2.

Andrew D Pucker,1 Chris Lievens,2 Gerald McGwin Jr,1 Quentin X Franklin,1 Amy Logan,1 Gregory S Wolfe2,3 1University of Alabama at Birmingham, Birmingham, AL, USA; 2Southern College of Optometry, Memphis, TN, USA; 3Center for Eye and Health Outcomes, Memphis, TN, USACorrespondence: Andrew D Pucker, University of Alabama at Birmingham, School of Optometry, 1716 University Blvd, Birmingham, AL, 35233, Tel +1 (920) 579-2900, Email apucker@uab.eduPurpose: To understand the impact of Systane Hydration PF on dryness symptoms and quality of life in digital device users and to determine if participants prefer either the unit-dose or multi-dose dispensing system of Systane Hydration PF.Materials and Methods: This 2-week, three visit study recruited regular digital device users. Participants were required to score ≤ 80 on the Impact of Dry Eye on Everyday Life (IDEEL) Quality of Life (QoL) Work domain and between 13 and 32 on the Ocular Surface Disease Index (OSDI) questionnaire. Participants were randomized to either Systane Hydration PF unit-dose or multi-dose for 1 week and switched to the alternative dosing system for the second week. Participations were evaluated by completing the full IDEEL-QoL module and OSDI questionnaire at each visit. Likert surveys were completed to probe dispensing system preferences.Results: Thirty participants with a mean ± SD age of 28.6 ± 12.0 years (70% female) were recruited. Participants had significant improvements in all three IDEEL-QoL domains as well as in OSDI scores (all p < 0.0001). Participants had similar preferences for the two dispensing systems, though they were more likely to indicate that they thought that the multi-dose bottle was more environmentally friendly than the unit-dose vials.Conclusion: Digital device users with dry eye symptoms had meaningful improvements in eye comfort and quality of life scores after being treated with Systane Hydration PF for 2 weeks. Participants did not have a clear dispensing system preference suggesting that the best dispensing system may depend on the patient.Keywords: artificial tears, digital eye strain, dry eye disease, symptoms, Systane Hydration PF

Abstract Synovium is critical for maintaining joint homeostasis and may contribute to mechanobiological responses during joint movement. We investigated mechanobiological responses of whole synovium from patients with late-stage knee osteoarthritis (OA). Synovium samples were collected during total knee arthroplasty and assigned to histopathology or cyclic 10% tensile strain loading, including (1) static (control); (2) low-frequency (0.3 Hz); and iii) high-frequency (1.0 Hz) for 30-min. After 6-h incubation, tissues were bisected for RNA isolation and immunostaining (3-nitrotyrosine; 3-NT). RNA sequencing was analyzed for differentially expressed genes and pathway enrichment. Cytokines and lactate were measured in conditioned media. Compared to controls, low-frequency strain induced enrichment of pathways related to interferon response, Fc-receptor signaling, and cell metabolism. High-frequency strain induced enrichment of pathways related to NOD-like receptor signaling, high metabolic demand, and redox signaling/stress. Metabolic and redox cell stress was confirmed by increased release of lactate into conditioned media and increased 3-NT formation in the synovial lining. Late-stage OA synovial tissue responses to tensile strain include frequency-dependent increases in inflammatory signaling, metabolism, and redox biology. Based on these findings, we speculate that some synovial mechanobiological responses to strain may be beneficial, but OA likely disturbs synovial homeostasis leading to aberrant responses to mechanical stimuli, which requires further validation.

Bone metastasis is highly prevalent in breast cancer patients with metastatic disease. These metastatic cells may eventually form osteolytic lesions and affect the integrity of the bone, causing pathological fractures and impairing patient quality of life. Although some mechanisms have been determined in the metastatic cascade to the bone, little is known about how the mechanical cues of the bone marrow microenvironment influence tumor cell growth and invasion once they have homed to the secondary site. The mechanical properties within the bone marrow range from 0.5 kPa in the sinusoidal region to 40 kPa in the endosteal region. Here, we report an alginate-Matrigel hydrogel that can be modulated to the stiffness range of the bone marrow and used to evaluate tumor cell behavior. We fabricated alginate-Matrigel hydrogels with varying calcium sulfate (CaSO4) concentrations to tune stiffness, and we demonstrated that these hydrogels recapitulated the mechanical properties observed in the bone marrow microenvironment (0.7–16 kPa). We encapsulated multiple breast cancer cell lines into these hydrogels to assess growth and invasion. Tumor cells in stiffer hydrogels exhibited increased proliferation and enhanced elongation compared to lower stiffness hydrogels, which suggests that stiffer environments in the bone marrow promote cellular invasive capacity. This work establishes a system that replicates bone marrow mechanical properties to elucidate the physical factors that contribute to metastatic growth.

The spiking activity of neocortical neurons exhibits a striking level of variability, even when these networks are driven by identical stimuli. The approximately Poisson firing of neurons has led to the hypothesis that these neural networks operate in the asynchronous state. In the asynchronous state, neurons fire independently from one another, so that the probability that a neuron experience synchronous synaptic inputs is exceedingly low. While the models of asynchronous neurons lead to observed spiking variability, it is not clear whether the asynchronous state can also account for the level of subthreshold membrane potential variability. We propose a new analytical framework to rigorously quantify the subthreshold variability of a single conductance-based neuron in response to synaptic inputs with prescribed degrees of synchrony. Technically, we leverage the theory of exchangeability to model input synchrony via jump-process-based synaptic drives; we then perform a moment analysis of the stationary response of a neuronal model with all-or-none conductances that neglects postspiking reset. As a result, we produce exact, interpretable closed forms for the first two stationary moments of the membrane voltage, with explicit dependence on the input synaptic numbers, strengths, and synchrony. For biophysically relevant parameters, we find that the asynchronous regime yields realistic subthreshold variability (voltage variance ≃4–9 mV^{2}) only when driven by a restricted number of large synapses, compatible with strong thalamic drive. By contrast, we find that achieving realistic subthreshold variability with dense cortico-cortical inputs requires including weak but nonzero input synchrony, consistent with measured pairwise spiking correlations. We also show that, without synchrony, the neural variability averages out to zero for all scaling limits with vanishing synaptic weights, independent of any balanced state hypothesis. This result challenges the theoretical basis for mean-field theories of the asynchronous state.

Titan is unique among the icy satellites in that it has a thick atmosphere, stable surficial bodies of liquid, and a precipitation system that promotes interactions between the two. Although Titan’s surface conditions are typically assumed to be above the freezing point temperatures of the major constituent species of the climate system (methane, ethane, and nitrogen), conditions may be sufficiently cool across parts of Titan to allow for ice formation alongside known liquid-vapor phases. In this study, we used Raman spectroscopy, visual inspection, and the CRYOCHEM 2.0 equation of state to map the appearance of first ice and to quantify the amount of nitrogen dissolution into liquid in the methane–ethane–nitrogen system along a 1.5 bar isobaric cooling path in the temperature range 80–95 K. This was with the intent of (1) determining the effects nitrogen has on the phase behaviors of the methane–ethane binary system, and (2) establishing the temperatures and ternary mixing ratios needed for ice formation on Titan’s surface. We found that ethane-rich mixtures enter a three-phase solid–liquid–vapor equilibrium and are characterized by nitrogen-rich exsolution upon freezing and ice that form at the bottom of the sample. With sufficient methane content, the mixtures cross a univariant four-phase solid–liquid–liquid–vapor boundary, which contributes to a distinct isothermal freezing point profile and ice that forms starting at the liquid–liquid interface. Our results generally agree with findings from previous studies of the methane–ethane–nitrogen system and are intended to add to our current understanding of Titan’s geochemical processes.

Summary: Social isolation (SI) is associated with an increased risk of mortality and various chronic diseases—including obesity—in humans. Murine studies probing SI metabolic outcomes remain inconsistent, due in part to a lack of consideration for housing temperature. Such experiments typically occur at room temperature, subjecting mice to chronic cold stress. Single housing prevents social thermoregulation, further exacerbating cold stress and obscuring psychosocial influences on metabolism at room temperature. In this study, C57BL/6 and BALB/c male mice were group- and single-housed under thermoneutral conditions to determine whether SI affects the development of high-fat diet-induced obesity. We report SI promotes weight gain, increases food intake, increases adiposity, worsens glycemic control, reduces insulin signaling, exacerbates systemic and adipose inflammatory responses, and induces a molecular signature within the hypothalamus. This study establishes a murine model that recapitulates the SI-induced propensity for obesity, which may further our understanding of SI’s influence on health and disease.

Abstract Understanding the relationship of population dynamics to density is central to many ecological investigations. Despite the importance of density-dependence in determining population growth, the empirical relationship between density and per capita growth remains understudied in most systems and is often assumed to be linear. In experimental studies of interspecific competition, investigators often evaluate the predicted outcomes by assuming such linear relationships, fitting linear functions, and estimating parameters of competition models. In this paper, we experimentally describe the shape of the relationship between estimated population rate of change and initial density using laboratory-reared populations of three mosquito species. We estimated per capita growth rate for these experimental populations over a 30-fold range of larval densities at a standard resource abundance. We then compared fits of linear models and several different nonlinear models for the relationship of estimated rate of change and density. We find that that the relationship between density and per capita growth is strongly non-linear in Aedes aegypti (Linnaeus), Aedes albopictus (Skuse), and Aedes triseriatus (Say) mosquitoes. Components of population growth (survivorship, development time, adult size) are also nonlinearly related to initial density. The causes and consequences of this nonlinearity are likely to be important issues for population and community ecology.

Abstract Background Autism spectrum disorder (ASD) involves complex genetics interacting with the perinatal environment, complicating the discovery of common genetic risk. The epigenetic layer of DNA methylation shows dynamic developmental changes and molecular memory of in utero experiences, particularly in placenta, a fetal tissue discarded at birth. However, current array-based methods to identify novel ASD risk genes lack coverage of the most structurally and epigenetically variable regions of the human genome. Results We use whole genome bisulfite sequencing in placenta samples from prospective ASD studies to discover a previously uncharacterized ASD risk gene, LOC105373085, renamed NHIP. Out of 134 differentially methylated regions associated with ASD in placental samples, a cluster at 22q13.33 corresponds to a 118-kb hypomethylated block that replicates in two additional cohorts. Within this locus, NHIP is functionally characterized as a nuclear peptide-encoding transcript with high expression in brain, and increased expression following neuronal differentiation or hypoxia, but decreased expression in ASD placenta and brain. NHIP overexpression increases cellular proliferation and alters expression of genes regulating synapses and neurogenesis, overlapping significantly with known ASD risk genes and NHIP-associated genes in ASD brain. A common structural variant disrupting the proximity of NHIP to a fetal brain enhancer is associated with NHIP expression and methylation levels and ASD risk, demonstrating a common genetic influence. Conclusions Together, these results identify and initially characterize a novel environmentally responsive ASD risk gene relevant to brain development in a hitherto under-characterized region of the human genome.

Context: Atlanto-occipital dissociation is a highly lethal ligamentous injury at the craniocervical junction (CCJ). Previous studies have described rare cases of milder forms of atlanto-occipital injury (AOI) which might be managed nonoperatively, but there is a paucity of literature on this subject. Aims: We retrospectively reviewed our institutional experience to characterize the injury patterns, treatments, and clinical courses of patients with unilateral AOI. Methods: We included patients with radiographic evidence of unilateral occipitocervical joint capsular disruption, distraction, or edema ± injury of the apical ligament, tectorial membrane, anterior atlanto-occipital membrane, posterior atlanto-occipital membrane, alar ligaments, or cruciate ligament. The long-term outcomes were gathered from medical records, and six patients were available for Neck Disability Index via phone call at the time of the study. Results: Eight patients were included in the study. The mean age was 45.1 years ± 26.5. Causes of trauma included motor vehicle collision for five patients (5/8, 62.5%), falls for two (2/8, 25), and assault for one (1/8, 12.5%). All patients had a widened condyle-C1 interval >2 mm. Three patients underwent occipitocervical fusion, one patient underwent atlantoaxial fusion, and another received subaxial fusions for other injuries. Three patients underwent no surgical intervention. All patients were seen at least once as an outpatient following hospital discharge. There were no delayed neurologic injuries or deaths. Conclusions: We propose that ligamentous injury at the CCJ functions more as a spectrum rather than dichotomous diagnosis, of which a subset can likely be safely managed nonoperatively.

Abstract Background Empiric antimalarial treatment is a component of protocol-based management of Ebola virus disease (EVD), yet this approach has limited clinical evidence for patient-centered benefits. Methods This retrospective cohort study evaluated the association between antimalarial treatment and mortality among patients with confirmed EVD. The data was collected from five International Medical Corps operated Ebola Treatment Units (ETUs) in Sierra Leone and Liberia from 2014 through 2015. The standardized protocol used for patient care included empiric oral treatment with combination artemether and lumefantrine, twice daily for three days; however, only a subset of patients received treatment due to resource variability. The outcome of interest was mortality, comparing patients treated with oral antimalarials within 48-h of admission to those not treated. Analysis was conducted with logistic regression to generate adjusted odds ratios (aORs). Multivariable analyses controlled for ETU country, malaria rapid diagnostic test result, age, EVD cycle threshold value, symptoms of bleeding, diarrhea, dysphagia and dyspnea, and additional standard clinical treatments. Results Among the 424 cases analyzed, 376 (88.7%) received early oral antimalarials. Across all cases, mortality occurred in 57.5% (244). In comparing unadjusted mortality prevalence, early antimalarial treated cases yielded 55.1% mortality versus 77.1% mortality for those untreated (p = 0.005). Multivariable analysis demonstrated evidence of reduced aOR for mortality with early oral antimalarial treatment versus non-treatment (aOR = 0.34, 95% Confidence Interval: 0.12, 0.92, p = 0.039). Conclusion Early oral antimalarial treatment in an EVD outbreak was associated with reduced mortality. Further study is warranted to investigate this association between early oral antimalarial treatment and mortality in EVD patients.

Background Predicting the need for post-traumatic reconstruction of lower extremity injuries remains a challenge. Due to the larger volume of cases in adults than in children, the majority of the medical literature has focused on adult lower extremity reconstruction. This study evaluates predictive risk factors associated with the need for free flap reconstruction in pediatric patients following lower extremity trauma. Methods An IRB-approved retrospective chart analysis over a 5-year period (January 1, 2012 to December 31, 2017) was performed, including all pediatric patients (

Background Immunotherapy has revolutionized clinical outcomes for patients suffering from lung cancer, yet relatively few patients sustain long-term durable responses. Recent studies have demonstrated that the tumor immune microenvironment fosters tumorous heterogeneity and mediates both disease progression and response to immune checkpoint inhibitors (ICI). As such, there is an unmet need to elucidate the spatially defined single-cell landscape of the lung cancer microenvironment to understand the mechanisms of disease progression and identify biomarkers of response to ICI.Methods Here, in this study, we applied imaging mass cytometry to characterize the tumor and immunological landscape of immunotherapy response in non-small cell lung cancer by describing activated cell states, cellular interactions and neighborhoods associated with improved efficacy. We functionally validated our findings using preclinical mouse models of cancer treated with anti-programmed cell death protein-1 (PD-1) immune checkpoint blockade.Results We resolved 114,524 single cells in 27 patients treated with ICI, enabling spatial resolution of immune lineages and activation states with distinct clinical outcomes. We demonstrated that CXCL13 expression is associated with ICI efficacy in patients, and that recombinant CXCL13 potentiates anti-PD-1 response in vivo in association with increased antigen experienced T cell subsets and reduced CCR2+ monocytes.Discussion Our results provide a high-resolution molecular resource and illustrate the importance of major immune lineages as well as their functional substates in understanding the role of the tumor immune microenvironment in response to ICIs.

Background: Lung cancer is the leading cause of cancer death in both men and women. Quebec has the highest lung cancer mortality out of all provinces in Canada, believed to be caused by higher smoking rates. Molecular testing for lung cancer is standard of care due to the discovery of actionable driver mutations that can be targeted with tyrosine kinase inhibitors. To date, no detailed molecular testing characterization of Quebec patients with lung cancer using next generation sequencing (NGS) has been performed. Materials and methods: The aim of this study was to describe the genomic landscape of patients with lung cancer (n = 997) who underwent NGS molecular testing at a tertiary care center in Quebec and to correlate it with clinical and pathology variables. Results: Compared to 10 other NGS studies found through a structured search strategy, our cohort had a higher prevalence of KRAS mutations (39.2%) compared to most geographical locations. Additionally, we observed a significant positive association between decreasing age and a higher proportion of KRAS G12C mutations. Conclusion: Overall, it remains important to assess institutional rates of actionable driver mutations to help guide governing bodies, fuel clinical trials and create benchmarks for expected rates as quality metrics.

Abstract Background Wildfires and forestry activities such as post-fire salvage logging are altering North American forests on a massive scale. Habitat change and fragmentation on forested landscapes may threaten forest specialists, such as Pacific marten (Martes caurina), that require closed, connected, and highly structured habitats. Although marten use burned landscapes, it is unclear how these animals respond to differing burn severities, or how well they tolerate additional landscape change from salvage logging. Methods We used snow tracking and GPS collars to examine marten movements in three large burns in north-central Washington, USA (burned in 2006) and central British Columbia, Canada (burned in 2010 and 2017). We also assessed marten habitat use in relation to areas salvage-logged in the 2010 burn. We evaluated marten path characteristics in relation to post-fire habitat quality, including shifts in behaviour when crossing severely-disturbed habitats. Using GPS locations, we investigated marten home range characteristics and habitat selection in relation to forest cover, burn severity, and salvage logging. Results Marten in the 2006 burn shifted from random to directed movement in areas burned at high severity; in BC, they chose highly straight paths when crossing salvage-blocks and meadows. Collared marten structured their home ranges around forest cover and burn severity, avoiding sparsely-covered habitats and selecting areas burned at low severity. Marten selected areas farther from roads in both Washington and BC, selected areas closer to water in the 2006 burn, and strongly avoided salvage-logged areas of the 2010 burn. Marten home ranges overlapped extensively, including two males tracked concurrently in the 2010 burn. Conclusions Areas burned at low severity provide critical habitat for marten post-fire. Encouragingly, our results indicate that both male and female marten can maintain home ranges in large burns and use a wide range of post-fire conditions. However, salvage-logged areas are not suitable for marten and may represent significant barriers to foraging and dispersal.