Tenofovir Douche as HIV Preexposure Prophylaxis for Receptive Anal Intercourse: Safety, Acceptability, Pharmacokinetics, and Pharmacodynamics (DREAM 01)

BACKGROUND

Despite highly effective HIV preexposure prophylaxis (PrEP) options, no options provide on-demand, nonsystemic, behaviorally congruent PrEP that many desire. A tenofovir-medicated rectal douche before receptive anal intercourse may provide this option.

METHODS

Three tenofovir rectal douches-220 mg iso-osmolar product A, 660 mg iso-osmolar product B, and 660 mg hypo-osmolar product C-were studied in 21 HIV-negative men who have sex with men. We sampled blood and colorectal tissue to assess safety, acceptability, pharmacokinetics, and pharmacodynamics.

RESULTS

The douches had high acceptability without toxicity. Median plasma tenofovir peak concentrations for all products were several-fold below trough concentrations associated with oral tenofovir disoproxil fumarate (TDF). Median colon tissue mucosal mononuclear cell (MMC) tenofovir-diphosphate concentrations exceeded target concentrations from 1 hour through 3 to 7 days after dosing. For 6-7 days after a single product C dose, MMC tenofovir-diphosphate exceeded concentrations expected with steady-state oral TDF 300 mg on-demand 2-1-1 dosing. Compared to predrug baseline, HIV replication after ex vivo colon tissue HIV challenge demonstrated a concentration-response relationship with 1.9 log10 maximal effect.

CONCLUSIONS

All 3 tenofovir douches achieved tissue tenofovir-diphosphate concentrations and colorectal antiviral effect exceeding oral TDF and with lower systemic tenofovir. Tenofovir douches may provide a single-dose, on-demand, behaviorally congruent PrEP option, and warrant continued development. Clinical Trials Registration . NCT02750540.

Prospective policy analysis-a critical interpretive synthesis review

Most policy analysis methods and approaches are applied retrospectively. As a result, there have been calls for more documentation of the political-economy factors central to health care reforms in real-time. We sought to highlight the methods and previous applications of prospective policy analysis (PPA) in the literature to document purposeful use of PPA and reflect on opportunities and drawbacks. We used a critical interpretive synthesis (CIS) approach as our initial scoping revealed that PPA is inconsistently defined in the literature. While we found several examples of PPA, all were researcher-led, most were published recently and few described mechanisms for engagement in the policy process. In addition, methods used were often summarily described and reported on relatively short prospective time horizons. Most of the studies stemmed from high-income countries and, across our sample, did not always clearly outline the rationale for a PPA and how this analysis was conceptualized. That only about one-fifth of the articles explicitly defined PPA underscores the fact that researchers and practitioners conducting PPA should better document their intent and reflect on key elements essential for PPA. Despite a wide recognition that policy processes are dynamic and ideally require multifaceted and longitudinal examination, the PPA approach is not currently frequently documented in the literature. However, the few articles reported in this paper might overestimate gaps in PPA applications. More likely, researchers are embedded in policy processes prospectively but do not necessarily write their articles from that perspective, and analyses led by non-academics might not make their way into the published literature. Future research should feature examples of testing and refining the proposed framework, as well as designing and reporting on PPA. Even when policy-maker engagement might not be feasible, real-time policy monitoring might have value in and of itself.

An Analysis of Social Determinants of Health and Their Implications for Hepatitis C Virus Treatment in People Who Inject Drugs: The Case of Baltimore

Background

Sixty-eight percent of the nearly 3.5 million people living with hepatitis C virus (HCV) in the United States are people who inject drugs (PWID). Despite effective treatments, uptake remains low in PWID. We examined the social determinants of health (SDoH) that affect the HCV care cascade.

Methods

We conducted a secondary analysis of data from 720 PWID in a cluster-randomized trial. We recruited PWID from 12 drug-affected areas in Baltimore. Inclusion criteria were injection in the prior month or needle sharing in the past 6 months. Intake data consisted of a survey and HCV testing. Focusing on SDoH, we analyzed self-report of (1) awareness of HCV infection (in those with active or previously cured HCV) and (2) prior HCV treatment (in the aware subgroup). We used descriptive statistics and logistic regression for statistical analyses.

Results

The 342 participants were majority male and Black with a median age of 52 years. Women were more likely to be aware of their status but less likely to be treated. Having a primary care provider and HIV-positive status were associated with increased awareness and treatment. Unhoused people had 51% lower odds of HCV treatment. People who reported that other PWID had shared their HCV status with them had 2.3-fold higher odds of awareness of their own status.

Conclusions

Further study of gender disparities in HCV treatment access is needed. Increased social support was associated with higher odds of HCV treatment, suggesting an area for future interventions. Strategies to identify and address SDoH are needed to end HCV.

Development of a Consensus-Based List of Potential Quality Indicators for Fever and Inflammation of Unknown Origin

With a growing emphasis on value-based reimbursement, developing quality indicators for infectious diseases has gained attention. Quality indicators for fever of unknown origin and inflammation of unknown origin are lacking. An assembled group of international experts developed 12 quality measures for these conditions, which could be validated with additional study.

Intimate partner violence and excess fertility among women of reproductive age in Malawi

PURPOSE

Gender inequity and adverse health outcomes continue to be of concern among women in sub-Saharan Africa. We determined prevalence of intimate partner violence and excess fertility (having more children than desired) in reproductive age women in Malawi. We also explored factors associated with these outcomes and with spousal fertility intentions.

PATIENTS AND METHODS

In a cross-sectional study, a total of 360 women and 410 men were recruited using multi-stage sampling from communities in a peri-urban setting in Blantyre District, Southern Malawi in 2021. Women and men were separately interviewed by trained study workers using a structured questionnaire. In addition to descriptive analyses, we used univariate and multivariate logistic regression models to assess associations of risk factors with the outcomes of intimate partner violence and excess fertility.

RESULTS

Among women, lifetime prevalence of intimate partner violence was 23.1%, and excess fertility was experienced by 25.6%. Intimate partner violence was associated with male partners alcohol consumption (adjusted odds ratio 2.13; P = 0.019). Women were more likely to report excess fertility if they were older (adjusted odds ratio 2.0, P<0.001, for a 5-year increase). Alcohol consumption by the male partner (adjusted odds ratio 2.14; P = 0.025) and women being able to refuse sex with their male partner (adjusted odds ratio 0.50; P = 0.036) were associated with discordant fertility preferences.

CONCLUSIONS

Intimate partner violence, excess fertility, and social and health inequities continue to be prevalent in Malawi. These data suggest the underlying proximal and distal factors associated with these adverse outcomes such as alcohol consumption may be addressed through education, couple interactive communication, and community dialogue. To ensure sustainability and effectiveness, strong leadership involvement, both governmental and non-governmental, is needed.

Co-transcriptional folding of the glmS ribozyme enables a rapid response to metabolite

The glmS ribozyme riboswitch, located in the 5' untranslated region of the Bacillus subtilis glmS messenger RNA (mRNA), regulates cell wall biosynthesis through ligand-induced self-cleavage and decay of the glmS mRNA. Although self-cleavage of the refolded glmS ribozyme has been studied extensively, it is not known how early the ribozyme folds and self-cleaves during transcription. Here, we combine single-molecule fluorescence with kinetic modeling to show that self-cleavage can occur during transcription before the ribozyme is fully synthesized. Moreover, co-transcriptional folding of the RNA at a physiological elongation rate allows the ribozyme catalytic core to react without the downstream peripheral stability domain. Dimethyl sulfate footprinting further revealed how slow sequential folding favors formation of the native core structure through fraying of misfolded helices and nucleation of a native pseudoknot. Ribozyme self-cleavage at an early stage of transcription may benefit glmS regulation in B. subtilis, as it exposes the mRNA to exoribonuclease before translation of the open reading frame can begin. Our results emphasize the importance of co-transcriptional folding of RNA tertiary structure for cis-regulation of mRNA stability.

Organogenetic transcriptomes of the Drosophila embryo at single cell resolution

To gain insight into the transcription programs activated during the formation of Drosophila larval structures, we carried out single cell RNA sequencing during two periods of Drosophila embryogenesis: stages 10-12, when most organs are first specified and initiate morphological and physiological specialization; and stages 13-16, when organs achieve their final mature architectures and begin to function. Our data confirm previous findings with regards to functional specialization of some organs - the salivary gland and trachea - and clarify the embryonic functions of another - the plasmatocytes. We also identify two early developmental trajectories in germ cells and uncover a potential role for proteolysis during germline stem cell specialization. We identify the likely cell type of origin for key components of the Drosophila matrisome and several commonly used Drosophila embryonic cell culture lines. Finally, we compare our findings with other recent related studies and with other modalities for identifying tissue-specific gene expression patterns. These data provide a useful community resource for identifying many new players in tissue-specific morphogenesis and functional specialization of developing organs.

Inclusive and intersectoral: community health improvement planning opportunities to advance the social determinants of health and health equity

BACKGROUND

Community health improvement plans (CHIPs) are strategic planning tools that help local communities identify and address their public health needs. Many local health departments have developed a CHIP, yet there is a lack of research on the extent to which these plans address root causes of health disparities such as the social determinants of health. This study aims to inventory the social determinants of health included in 13 CHIPs and examine facilitators and challenges faced by local health departments and partners when trying to include the social determinants of health.

METHODS

We conducted a comparative plan evaluation by scoring 13 CHIPs on their inclusion of equity orientation, inclusive planning processes, and five social determinants of health: health care access and quality, the neighborhood and built environment, economic stability, social and community context, and education access and quality. To supplement the plan evaluation, we conducted 32 in-depth interviews with CHIP leaders and stakeholders to understand the factors contributing to the inclusion and exclusion of the social determinants of health in the planning process.

RESULTS

CHIPs received an average score of 49/100 for the inclusion of the social determinants of health. Most plans addressed health care access and quality and the neighborhood and built environment, but they often did not address economic stability, the social and community context, and education access and quality. Regarding their overall equity orientation, CHIPs received an average score of 35/100, reflecting a relative lack of attention to equity and inclusive planning processes in the plans. Interviews revealed that challenges engaging partners, making clear connections between CHIPs and social determinants, and a lack of capacity or public and partner support often led to the exclusion of the social determinants of health. Recommendations to improve planning processes include improving data infrastructure, providing resources for dedicated planning staff and community engagement incentives, and centering equity throughout the planning process.

CONCLUSIONS

Although local health departments can leverage CHIPs to improve population health and address health disparities, they face a range of challenges to including the social determinants of health in CHIPs. Additional resourcing and improved data are needed to facilitate broader inclusion of these determinants, and more work is needed to elevate equity throughout these planning processes.

Physicians' Hierarchy of Tumor Biomarkers for Optimizing Chemotherapy in Breast Cancer Care

BACKGROUND

Tumor biomarkers are regularly used to guide breast cancer treatment and clinical trial enrollment. However, there remains a lack of knowledge regarding physicians' perspectives towards biomarkers and their role in treatment optimization, where treatment intensity is reduced to minimize toxicity.

METHODS

Thirty-nine academic and community oncologists participated in semi-structured qualitative interviews, providing perspectives on optimization approaches to chemotherapy treatment. Interviews were audio-recorded, transcribed, and analyzed by 2 independent coders utilizing a constant comparative method in NVivo. Major themes and exemplary quotes were extracted. A framework outlining physicians' conception of biomarkers, and their comfortability with their use in treatment optimization, was developed.

RESULTS

In the hierarchal model of biomarkers, level 1 is comprised of standard-of-care (SoC) biomarkers, defined by a strong level of evidence, alignment with national guidelines, and widespread utilization. Level 2 includes SoC biomarkers used in alternative contexts, in which physicians expressed confidence, yet less certainty, due to a lack of data in certain subgroups. Level 3, or experimental, biomarkers created the most diverse concerns related to quality and quantity of evidence, with several additional modulators.

CONCLUSION

This study demonstrates that physicians conceptualize the use of biomarkers for treatment optimization in successive levels. This hierarchy can be used to guide trialists in the development of novel biomarkers and design of future trials.

The C-Terminal of NaV1.7 Is Ubiquitinated by NEDD4L

NaV1.7, the neuronal voltage-gated sodium channel isoform, plays an important role in the human body's ability to feel pain. Mutations within NaV1.7 have been linked to pain-related syndromes, such as insensitivity to pain. To date, the regulation and internalization mechanisms of the NaV1.7 channel are not well known at a biochemical level. In this study, we perform biochemical and biophysical analyses that establish that the HECT-type E3 ligase, NEDD4L, ubiquitinates the cytoplasmic C-terminal (CT) region of NaV1.7. Through in vitro ubiquitination and mass spectrometry experiments, we identify, for the first time, the lysine residues of NaV1.7 within the CT region that get ubiquitinated. Furthermore, binding studies with an NEDD4L E3 ligase modulator (ubiquitin variant) highlight the dynamic partnership between NEDD4L and NaV1.7. These investigations provide a framework for understanding how NEDD4L-dependent regulation of the channel can influence the NaV1.7 function.

Age-associated changes in lineage composition of the enteric nervous system regulate gut health and disease

The enteric nervous system (ENS), a collection of neural cells contained in the wall of the gut, is of fundamental importance to gastrointestinal and systemic health. According to the prevailing paradigm, the ENS arises from progenitor cells migrating from the neural crest and remains largely unchanged thereafter. Here, we show that the lineage composition of maturing ENS changes with time, with a decline in the canonical lineage of neural-crest derived neurons and their replacement by a newly identified lineage of mesoderm-derived neurons. Single cell transcriptomics and immunochemical approaches establish a distinct expression profile of mesoderm-derived neurons. The dynamic balance between the proportions of neurons from these two different lineages in the post-natal gut is dependent on the availability of their respective trophic signals, GDNF-RET and HGF-MET. With increasing age, the mesoderm-derived neurons become the dominant form of neurons in the ENS, a change associated with significant functional effects on intestinal motility which can be reversed by GDNF supplementation. Transcriptomic analyses of human gut tissues show reduced GDNF-RET signaling in patients with intestinal dysmotility which is associated with reduction in neural crest-derived neuronal markers and concomitant increase in transcriptional patterns specific to mesoderm-derived neurons. Normal intestinal function in the adult gastrointestinal tract therefore appears to require an optimal balance between these two distinct lineages within the ENS.

Neurocognitive Correlates of Clinical Decision Making: A Pilot Study Using Electroencephalography

The development of sound clinical reasoning, while essential for optimal patient care, can be quite an elusive process. Researchers typically rely on a self-report or observational measures to study decision making, but clinicians' reasoning processes may not be apparent to themselves or outside observers. This study explored electroencephalography (EEG) to examine neurocognitive correlates of clinical decision making during a simulated American Board of Anesthesiology-style standardized oral exam. Eight novice anesthesiology residents and eight fellows who had recently passed their board exams were included in the study. Measures included EEG recordings from each participant, demographic information, self-reported cognitive load, and observed performance. To examine neurocognitive correlates of clinical decision making, power spectral density (PSD) and functional connectivity between pairs of EEG channels were analyzed. Although both groups reported similar cognitive load (p = 0.840), fellows outperformed novices based on performance scores (p < 0.001). PSD showed no significant differences between the groups. Several coherence features showed significant differences between fellows and residents, mostly related to the channels within the frontal, between the frontal and parietal, and between the frontal and temporal areas. The functional connectivity patterns found in this study could provide some clues for future hypothesis-driven studies in examining the underlying cognitive processes that lead to better clinical reasoning.

Distance and destination of retail meat alter multidrug resistant contamination in the United States food system

Antibiotic-resistant infections are a global concern, especially those caused by multidrug-resistant (MDR) bacteria, defined as those resistant to more than three drug classes. The animal agriculture industry contributes to the antimicrobial resistant foodborne illness burden via contaminated retail meat. In the United States, retail meat is shipped across the country. Therefore, understanding geospatial factors that influence MDR bacterial contamination is vital to protect consumers and inform interventions. Using data available from the United States Food and Drug Administration's National Antimicrobial Resistance Monitoring System (NARMS), we describe retail meat shipping distances using processor and retailer locations and investigated this distance as a risk factor for MDR bacteria meat contamination using log-binomial regression. Meat samples collected during 2012-2014 totaled 11,243, of which 4791 (42.61%) were contaminated with bacteria and 835 (17.43%) of those bacteria were MDR. All examined geospatial factors were associated with MDR bacteria meat contamination. After adjustment for year and meat type, we found higher prevalence of MDR contamination among meat processed in the south (relative adjusted prevalence ratio [aPR] 1.35; 95% CI 1.06-1.73 when compared to the next-highest region), sold in Maryland (aPR 1.12; 95% CI 0.95-1.32 when compared to the next-highest state), and shipped from 194 to 469 miles (aPR 1.59; 95% CI 1.31-1.94 when compared to meats that traveled < 194 miles). However, sensitivity analyses revealed that New York sold the meat with the highest prevalence of MDR Salmonella contamination (4.84%). In this secondary analysis of NARMS data, both geographic location where products were sold and the shipping distance were associated with microbial contamination on retail meat.

Directing Uphill Strand Displacement with an Engineered Superhelicase

The ability to finely tune reaction rates and binding energies between components has made DNA strand displacement circuits promising candidates to replicate the complex regulatory functions of biological reaction networks. However, these circuits often lack crucial properties, such as signal turnover and the ability to transiently respond to successive input signals that require the continuous input of chemical energy. Here, we introduce a method for providing such energy to strand displacement networks in a controlled fashion: an engineered DNA helicase, Rep-X, that transiently dehybridizes specific DNA complexes, enabling the strands in the complex to participate in downstream hybridization or strand displacement reactions. We demonstrate how this process can direct the formation of specific metastable structures by design and that this dehybridization process can be controlled by DNA strand displacement reactions that effectively protect and deprotect a double-stranded complex from unwinding by Rep-X. These findings can guide the design of active DNA strand displacement regulatory networks, in which sustained dynamical behavior is fueled by helicase-regulated unwinding.

Biased placement of Mitochondria fission facilitates asymmetric inheritance of protein aggregates during yeast cell division

Mitochondria are essential and dynamic eukaryotic organelles that must be inherited during cell division. In yeast, mitochondria are inherited asymmetrically based on quality, which is thought to be vital for maintaining a rejuvenated cell population; however, the mechanisms underlying mitochondrial remodeling and segregation during this process are not understood. We used high spatiotemporal imaging to quantify the key aspects of mitochondrial dynamics, including motility, fission, and fusion characteristics, upon aggregation of misfolded proteins in the mitochondrial matrix. Using these measured parameters, we developed an agent-based stochastic model of dynamics of mitochondrial inheritance. Our model predicts that biased mitochondrial fission near the protein aggregates facilitates the clustering of protein aggregates in the mitochondrial matrix, and this process underlies asymmetric mitochondria inheritance. These predictions are supported by live-cell imaging experiments where mitochondrial fission was perturbed. Our findings therefore uncover an unexpected role of mitochondrial dynamics in asymmetric mitochondrial inheritance.

"It was almost like it's set up for people to fail" A qualitative analysis of experiences and unmet supportive needs of people with Long COVID

BACKGROUND

Almost twenty percent of adults with COVID-19 develop Long COVID, leading to prolonged symptoms and disability. Understanding the supportive needs of people with Long COVID is vital to enacting effective models of care and policies.

DESIGN/METHODS

This qualitative sub-study explored the experiences of people with Long COVID and their unmet needs. Participants enrolled in a larger study to evaluate the post-acute cardiovascular impacts of COVID-19 were invited to participate in subsequent in-depth interviews. Participants were enrolled purposively until saturation at 24 participants. Data were analyzed using thematic content analysis.

RESULTS

Participants focused on adaptations to life with Long COVID and their unmet needs in different life spheres. Three domains, 1) occupational and financial; 2) healthcare-related; and 3) social and emotional support, emerged as areas affecting quality of life. Although participants were motivated to return to work for financial and personal reasons, Long COVID symptoms often resulted in the inability to perform tasks required by their existing jobs, and unemployment. Those who maintained employment through employer accommodations still needed additional support. Participants encountered diagnostic challenges, challenges in accessing specialty appointments, insurance loopholes, high healthcare costs, and medical skepticism. Existing social networks provided support for completing daily tasks; however, those with Long COVID typically turned to others with similar lived experiences for emotional support. Participants found government support programs inadequate and difficult to access in all three domains.

DISCUSSION

We propose a five-pronged policy approach to support persons with Long COVID. These overarching recommendations are (1) improve public awareness of Long COVID; (2) improve clinical care quality and access; (3) implement additional school and workplace accommodations; (4) strengthen socioeconomic benefits and social services; and (5) improve research on Long COVID.

Predicting ventricular tachycardia circuits in patients with arrhythmogenic right ventricular cardiomyopathy using genotype-specific heart digital twins

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic cardiac disease that leads to ventricular tachycardia (VT), a life-threatening heart rhythm disorder. Treating ARVC remains challenging due to the complex underlying arrhythmogenic mechanisms, which involve structural and electrophysiological (EP) remodeling. Here, we developed a novel genotype-specific heart digital twin (Geno-DT) approach to investigate the role of pathophysiological remodeling in sustaining VT reentrant circuits and to predict the VT circuits in ARVC patients of different genotypes. This approach integrates the patient's disease-induced structural remodeling reconstructed from contrast-enhanced magnetic-resonance imaging and genotype-specific cellular EP properties. In our retrospective study of 16 ARVC patients with two genotypes: plakophilin-2 (PKP2, n = 8) and gene-elusive (GE, n = 8), we found that Geno-DT accurately and non-invasively predicted the VT circuit locations for both genotypes (with 100%, 94%, 96% sensitivity, specificity, and accuracy for GE patient group, and 86%, 90%, 89% sensitivity, specificity, and accuracy for PKP2 patient group), when compared to VT circuit locations identified during clinical EP studies. Moreover, our results revealed that the underlying VT mechanisms differ among ARVC genotypes. We determined that in GE patients, fibrotic remodeling is the primary contributor to VT circuits, while in PKP2 patients, slowed conduction velocity and altered restitution properties of cardiac tissue, in addition to the structural substrate, are directly responsible for the formation of VT circuits. Our novel Geno-DT approach has the potential to augment therapeutic precision in the clinical setting and lead to more personalized treatment strategies in ARVC.

A data-driven framework for structure-property correlation in ordered and disordered cellular metamaterials

Extracting the relation between microstructural features and resulting material properties is essential for advancing our fundamental knowledge on the mechanics of cellular metamaterials and to enable the design of novel material systems. Here, we present a unified framework that not only allows the prediction of macroscopic properties but, more importantly, also reveals their connection to key morphological characteristics, as identified by the integration of machine-learning models and interpretability algorithms. We establish the complex manner in which strut orientation can be critical in determining effective stiffness for certain microstructures and highlight cellular metamaterials with counterintuitive material behavior. We further provide a refined version of Maxwell's criteria regarding the rigidity of frame structures and their connection to cellular metamaterials. By examining the shear moduli of these metamaterials, the mean cell compactness emerges as a key morphological feature. The generality of the proposed framework allows its extension to broader classes of architected materials as well as different properties of interest.

Chromatin and gene expression changes during female Drosophila germline stem cell development illuminate the biology of highly potent stem cells

Highly potent animal stem cells either self renew or launch complex differentiation programs, using mechanisms that are only partly understood. Drosophila female germline stem cells (GSCs) perpetuate without change over evolutionary time and generate cystoblast daughters that develop into nurse cells and oocytes. Cystoblasts initiate differentiation by generating a transient syncytial state, the germline cyst, and by increasing pericentromeric H3K9me3 modification, actions likely to suppress transposable element activity. Relatively open GSC chromatin is further restricted by Polycomb repression of testis or somatic cell-expressed genes briefly active in early female germ cells. Subsequently, Neijre/CBP and Myc help upregulate growth and reprogram GSC metabolism by altering mitochondrial transmembrane transport, gluconeogenesis, and other processes. In all these respects GSC differentiation resembles development of the totipotent zygote. We propose that the totipotent stem cell state was shaped by the need to resist transposon activity over evolutionary timescales.

The Curvature, Collagen Network Structure, and Their Relationship to the Pressure-Induced Strain Response of the Human Lamina Cribrosa in Normal and Glaucoma Eyes

The lamina cribrosa (LC) is a connective tissue in the optic nerve head (ONH). The objective of this study was to measure the curvature and collagen microstructure of the human LC, compare the effects of glaucoma and glaucoma optic nerve damage, and investigate the relationship between the structure and pressure-induced strain response of the LC in glaucoma eyes. Previously, the posterior scleral cups of 10 normal eyes and 16 diagnosed glaucoma eyes were subjected to inflation testing with second harmonic generation (SHG) imaging of the LC and digital volume correlation (DVC) to calculate the strain field. In this study, we applied a custom microstructural analysis algorithm to the maximum intensity projection of SHG images to measure features of the LC beam and pore network. We also estimated the LC curvatures from the anterior surface of the DVC-correlated LC volume. Results showed that the LC in glaucoma eyes had larger curvatures p≤0.03), a smaller average pore area (p = 0.001), greater beam tortuosity (p < 0.0001), and more isotropic beam structure (p = 0.01) than in normal eyes. The difference measured between glaucoma and normal eyes may indicate remodeling of the LC with glaucoma or baseline differences that contribute to the development of glaucomatous axonal damage.

Effects of oral Δ9-tetrahydrocannabinol and cannabidiol combinations on a sustained attention task in rats

A well-documented side effect of cannabis and Δ9-tetrahydrocannabinol (THC) acute administration is deficits in cognition and attention. Cannabidiol (CBD), a nonintoxicating constituent of cannabis, may modulate THC's impairing effects. A goal of this study was to determine the effects of THC and CBD, alone and in combination, on performance in the rodent Psychomotor Vigilance Test (rPVT), a translational paradigm used to quantify sustained attention. Outcome measures in the rPVT include motor speed, premature responding, and lapses in attention. Sprague Dawley rats were trained to perform the rPVT to the acquisition criteria and then received oral doses (mg/kg) of THC (1-17.6), CBD (1-100), and combinations of THC + CBD in sesame oil prior to rPVT sessions, administered in a within-subject randomized design. Blood was collected from rats receiving selected doses of THC alone or THC + CBD for analysis of THC and its metabolites. THC alone produced significant decreases in accuracy and increases in lapses in attention at higher doses (10 mg/kg; ps < .05). The coadministration of CBD (10 mg/kg) with THC (3 or 10 mg/kg) caused greater impairments to sustained attention compared with administration of THC alone (ps < .05). The rPVT is a translational platform sensitive to detect impairments in attention associated with THC and other cannabis constituents. Further work is necessary to determine the mechanism of THC and CBD interactions on impairments in sustained attention. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Effect of recombination on genetic diversity of Caenorhabditis elegans

Greater molecular divergence and genetic diversity are present in regions of high recombination in many species. Studies describing the correlation between variant abundance and recombination rate have long focused on recombination in the context of linked selection models, whereby interference between linked sites under positive or negative selection reduces genetic diversity in regions of low recombination. Here, we show that indels, especially those of intermediate sizes, are enriched relative to single nucleotide polymorphisms in regions of high recombination in C. elegans. To explain this phenomenon, we reintroduce an alternative model that emphasizes the mutagenic effect of recombination. To extend the analysis, we examine the variants with a phylogenetic context and discuss how different models could be examined together. The number of variants generated by recombination in natural populations could be substantial including possibly the majority of some indel subtypes. Our work highlights the potential importance of a mutagenic effect of recombination, which could have a significant role in the shaping of natural genetic diversity.

Characterizing metals in particulate pollution in communities at the fenceline of heavy industry: combining mobile monitoring and size-resolved filter measurements

Exposures to metals from industrial emissions can pose important health risks. The Chester-Trainer-Marcus Hook area of southeastern Pennsylvania is home to multiple petrochemical plants, a refinery, and a waste incinerator, most abutting socio-economically disadvantaged residential communities. Existing information on fenceline community exposures is based on monitoring data with low temporal and spatial resolution and EPA models that incorporate industry self-reporting. During a 3 week sampling campaign in September 2021, size-resolved particulate matter (PM) metals concentrations were obtained at a fixed site in Chester and on-line mobile aerosol measurements were conducted around Chester-Trainer-Marcus Hook. Fixed-site arsenic, lead, antimony, cobalt, and manganese concentrations in total PM were higher (p < 0.001) than EPA model estimates, and arsenic, lead, and cadmium were predominantly observed in fine PM (<2.5 μm), the PM fraction which can penetrate deeply into the lungs. Hazard index analysis suggests adverse effects are not expected from exposures at the observed levels; however, additional chemical exposures, PM size fraction, and non-chemical stressors should be considered in future studies for accurate assessment of risk. Fixed-site MOUDI and nearby mobile aerosol measurements were moderately correlated (r ≥ 0.5) for aluminum, potassium and selenium. Source apportionment analyses suggested the presence of four major emissions sources (sea salt, mineral dust, general combustion, and non-exhaust vehicle emissions) in the study area. Elevated levels of combustion-related elements of health concern (e.g., arsenic, cadmium, antimony, and vanadium) were observed near the waste incinerator and other industrial facilities by mobile monitoring, as well as in residential-zoned areas in Chester. These results suggest potential co-exposures to harmful atmospheric metal/metalloids in communities surrounding the Chester-Trainer-Marcus Hook industrial area at levels that may exceed previous estimates from EPA modeling.

Surveillance and treatment of primary hepatocellular carcinoma (aka. STOP HCC): protocol for a prospective cohort study of high-risk patients for HCC using GALAD-score

BACKGROUND

Vietnam and Saudi Arabia have high disease burden of primary hepatocellular carcinoma (HCC). Early detection in asymptomatic patients at risk for HCC is a strategy to improve survival outcomes in HCC management. GALAD score, a serum-based panel, has demonstrated promising clinical utility in HCC management. However, in order to ascertain its potential role in the surveillance of the early detection of HCC, GALAD needs to be validated prospectively for clinical surveillance of HCC (i.e., phase IV biomarker validation study). Thus, we propose to conduct a phase IV biomarker validation study to prospectively survey a cohort of patients with advanced fibrosis or compensated cirrhosis, irrespective of etiologies, using semi-annual abdominal ultrasound and GALAD score for five years.

METHODS

We plan to recruit a cohort of 1,600 patients, male or female, with advanced fibrosis or cirrhosis (i.e., F3 or F4) and MELD ≤ 15, in Vietnam and Saudi Arabia (n = 800 each). Individuals with a liver mass ≥ 1 cm in diameter, elevated alpha-fetoprotein (AFP) (≥ 9 ng/mL), and/or elevated GALAD score (≥ -0.63) will be scanned with dynamic contrast-enhanced magnetic resonance imaging (MRI), and a diagnosis of HCC will be made by Liver Imaging Reporting and Data System (LiRADS) assessment (LiRADS-5). Additionally, those who do not exhibit abnormal imaging findings, elevated AFP titer, and/or elevated GALAD score will obtain a dynamic contrast-enhanced MRI annually for five years to assess for HCC. Only MRI nearest to the time of GALAD score measurement, ultrasound and/or AFP evaluation will be included in the diagnostic validation analysis. MRI will be replaced with an abdominal computed tomography scan when MRI results are poor due to patient conditions such as movement etc. Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced MRI will not be carried out in study sites in both countries. Bootstrap resampling technique will be used to account for repeated measures to estimate standard errors and confidence intervals. Additionally, we will use the Cox proportional hazards regression model with covariates tailored to the hypothesis under investigation for time-to-HCC data as predicted by time-varying biomarker data.

DISCUSSION

The present work will evaluate the performance of GALAD score in early detection of liver cancer. Furthermore, by leveraging the prospective cohort, we will establish a biorepository of longitudinally collected biospecimens from patients with advanced fibrosis or cirrhosis to be used as a reference set for future research in early detection of HCC in the two countries.

TRIAL REGISTRATION

Name of the registry: ClinicalTrials.gov Registration date: 22 April 2022 Trial registration number: NCT05342350 URL of trial registry record.

Do striking biases in mass inference reflect a flawed mental model of physics?

To engage with the physical world, we rely on our intuitive sense of how objects will behave when we act on them or they interact with each other. Objects' latent properties such as mass and hardness determine how their physical interactions will unfold, and people have a keen ability to infer these latent properties by observing physical events. For example, we can precisely discriminate the relative masses of two objects when we see them collide. However, such inferences are sometimes subject to marked biases. When inferring mass from an observed collision, people consistently overestimate the mass of an incoming object that strikes a stationary one. Why? A number of plausible accounts have been put forward, variously arguing that the bias arises from rule-based reasoning, oversimplified stimuli, or noisy perceptual estimates of the scene dynamics. The implications of these views stand in stark contrast to one another: systematic biases may reveal a fundamental deficiency in the mental model of physical behavior, or they may be an expected consequence of reasoning over imperfect information. Here, we investigated all three accounts within a unified paradigm, presenting videos of real-world bowling ball collisions. We found that using richly detailed stimuli did not eliminate biases in mass inference. However, individual differences in the biases were task-specific and well-explained by noisy perceptual estimates rather than oversimplified physical inference mechanisms. Our findings collectively point toward an intuitive physics system that implements Newtonian principles but is subject to the quality of the information it operates on. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

LATE-NC risk alleles (in TMEM106B, GRN, and ABCC9 genes) among persons with African ancestry

Limbic-predominant age-related TDP-43 encephalopathy (LATE) affects approximately one-third of older individuals and is associated with cognitive impairment. However, there is a highly incomplete understanding of the genetic determinants of LATE neuropathologic changes (LATE-NC) in diverse populations. The defining neuropathologic feature of LATE-NC is TDP-43 proteinopathy, often with comorbid hippocampal sclerosis (HS). In terms of genetic risk factors, LATE-NC and/or HS are associated with single nucleotide variants (SNVs) in 3 genes-TMEM106B (rs1990622), GRN (rs5848), and ABCC9 (rs1914361 and rs701478). We evaluated these 3 genes in convenience samples of individuals of African ancestry. The allele frequencies of the LATE-associated alleles were significantly different between persons of primarily African (versus European) ancestry: In persons of African ancestry, the risk-associated alleles for TMEM106B and ABCC9 were less frequent, whereas the risk allele in GRN was more frequent. We performed an exploratory analysis of data from African-American subjects processed by the Alzheimer's Disease Genomics Consortium, with a subset of African-American participants (n = 166) having corroborating neuropathologic data through the National Alzheimer's Coordinating Center (NACC). In this limited-size sample, the ABCC9/rs1914361 SNV was associated with HS pathology. More work is required concerning the genetic factors influencing non-Alzheimer disease pathology such as LATE-NC in diverse cohorts.

Risk of Hepatocellular Carcinoma After Spontaneous Clearance of Hepatitis C Virus and in Noncirrhosis Chronic Hepatitis C Patients With Sustained Virological Response: A Systematic Review

In a hepatitis C virus (HCV)-controlled human infection model (CHIM), healthy volunteers are inoculated with HCV and then treated. Residual hepatocellular carcinoma (HCC) risk after viral clearance is an important consideration when evaluating the CHIM. We estimate HCC risk in spontaneously cleared HCV and in noncirrhosis after sustained virological response (SVR) to HCV treatment in a systematic review and using data from 3 cohorts: German anti-D, Taiwan, and US Veterans Affairs (VA). For noncirrhosis SVR, the overall HCC rate is 0.33 per 100 patient-years in meta-analysis. HCC rates for the German, Taiwan, and US Veterans Affairs cohorts are 0, 0.14, and 0.02 per 100 patient-years, respectively. Past hepatitis B virus exposure was not accounted for in the Taiwan cohort, while VA patients were likely tested based on liver disease/risk factors, which may confound HCC outcomes. The German cohort with no HCC after 44 years is most comparable to the CHIM participants. Although it is difficult to precisely estimate HCC risk from an HCV CHIM, the data suggest the risk to be very low or negligible.

Challenge Inoculum for Hepatitis C Virus Controlled Human Infection Model

For any controlled human infection model (CHIM), a safe, standardized, and biologically relevant challenge inoculum is necessary. For hepatitis C virus (HCV) CHIM, we propose that human-derived high-titer inocula of several viral genotypes with extensive virologic, serologic, and molecular characterizations should be the most appropriate approach. These inocula should first be tested in human volunteers in a step-wise manner to ensure safety, reproducibility, and curability prior to using them for testing the efficacy of candidate vaccines.

Transfer learning in a biomaterial fibrosis model identifies in vivo senescence heterogeneity and contributions to vascularization and matrix production across species and diverse pathologies

Cellular senescence is a state of permanent growth arrest that plays an important role in wound healing, tissue fibrosis, and tumor suppression. Despite senescent cells' (SnCs) pathological role and therapeutic interest, their phenotype in vivo remains poorly defined. Here, we developed an in vivo-derived senescence signature (SenSig) using a foreign body response-driven fibrosis model in a p16-CreERT2;Ai14 reporter mouse. We identified pericytes and "cartilage-like" fibroblasts as senescent and defined cell type-specific senescence-associated secretory phenotypes (SASPs). Transfer learning and senescence scoring identified these two SnC populations along with endothelial and epithelial SnCs in new and publicly available murine and human data single-cell RNA sequencing (scRNAseq) datasets from diverse pathologies. Signaling analysis uncovered crosstalk between SnCs and myeloid cells via an IL34-CSF1R-TGFβR signaling axis, contributing to tissue balance of vascularization and matrix production. Overall, our study provides a senescence signature and a computational approach that may be broadly applied to identify SnC transcriptional profiles and SASP factors in wound healing, aging, and other pathologies.

Health Insurance and Initiation of Direct-Acting Antivirals for Hepatitis C in US Women With Human Immunodeficiency Virus

BACKGROUND

Direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) is well tolerated, cost-effective, and yields high sustained virologic response rates, yet it has remained financially inaccessible to many patients.

METHODS

Participants of the Women's Interagency HIV Study (an observational US cohort) with human immunodeficiency virus (HIV) and HCV (RNA+) reporting no prior hepatitis C treatment were followed for DAA initiation (2015-2019). We estimated risk ratios (RRs) of the relationship between time-varying health insurance status and DAA initiation, adjusting for confounders with stabilized inverse probability weights. We also estimated weighted cumulative incidences of DAA initiation by health insurance status.

RESULTS

A total of 139 women (74% Black) were included; at baseline, the median age was 55 years and 86% were insured. Most had annual household incomes ≤$18 000 (85%); advanced liver fibrosis (21%), alcohol use (45%), and recreational drug use (35%) were common. Across 439 subsequent semiannual visits, 88 women (63%) reported DAA initiation. Compared with no health insurance, health insurance increased the likelihood of reporting DAA initiation at a given visit (RR, 4.94; 95% confidence limit [CL], 1.92 to 12.8). At 2 years, the weighted cumulative incidence of DAA initiation was higher among the insured (51.2%; 95% CL, 43.3% to 60.6%) than the uninsured (3.5%; 95% CL, 0.8% to 14.6%).

CONCLUSIONS

Accounting for clinical, behavioral, and sociodemographic factors over time, health insurance had a substantial positive effect on DAA initiation. Interventions to increase insurance coverage should be prioritized to increase HCV curative therapy uptake for persons with HIV.

A novel virtual course to teach medical students high-value decision-making

BACKGROUND

Although a clinician's ability to employ high-value decision-making is influenced by training, many undergraduate medical education programmes lack a formal curriculum in high-value, cost-conscious care. We present a curriculum developed through a cross-institutional collaboration that was used to teach students at two institutions about this topic and can serve as a framework for other institutions to develop similar curricula.

APPROACH

The faculty from the University of Virginia and the Johns Hopkins University School of Medicine created a 2-week-long online course to teach medical students the fundamentals of high-value care. The course consisted of learning modules, clinical cases, textbook studies, journal clubs and a competitive 'Shark Tank' final project where students proposed a realistic intervention to promote high-value clinical care.

EVALUATION

Over two-thirds of students rated the course's quality as excellent or very good. Most found the online modules (92%), assigned textbook readings (89%) and 'Shark Tank' competition (83%) useful. To evaluate the student's ability to apply the concepts learned during the course in clinical contexts, we developed a scoring rubric based on the New World Kirkpatrick Model to evaluate students' proposals. Groups chosen as finalists (as determined by faculty judges) were more likely to be fourth-year students (56%), achieved higher overall scores (p = 0.03), better incorporated cost impact at several levels (patient, hospital and national) (p = 0.001) and discussed both positive and negative impacts on patient safety (p = 0.04).

IMPLICATIONS

This course provides a framework for medical schools to use in their teaching of high-value care. Cross-institutional collaboration and online content overcame local barriers such as contextual factors and lack of faculty expertise, allowed for greater flexibility, and enabled focused curricular time to be spent on a capstone project competition. Prior clinical experience amongst medical students may be an enabling factor in promoting application of learning related to high-value care.

Cuticular profiling of insecticide resistant Aedes aegypti

Insecticides have made great strides in reducing the global burden of vector-borne disease. Nonetheless, serious public health concerns remain because insecticide-resistant vector populations continue to spread globally. To circumvent insecticide resistance, it is essential to understand all contributing mechanisms. Contact-based insecticides are absorbed through the insect cuticle, which is comprised mainly of chitin polysaccharides, cuticular proteins, hydrocarbons, and phenolic biopolymers sclerotin and melanin. Cuticle interface alterations can slow or prevent insecticide penetration in a phenomenon referred to as cuticular resistance. Cuticular resistance characterization of the yellow fever mosquito, Aedes aegypti, is lacking. In the current study, we utilized solid-state nuclear magnetic resonance spectroscopy, gas chromatography/mass spectrometry, and transmission electron microscopy to gain insights into the cuticle composition of congenic cytochrome P450 monooxygenase insecticide resistant and susceptible Ae. aegypti. No differences in cuticular hydrocarbon content or phenolic biopolymer deposition were found. In contrast, we observed cuticle thickness of insecticide resistant Ae. aegypti increased over time and exhibited higher polysaccharide abundance. Moreover, we found these local cuticular changes correlated with global metabolic differences in the whole mosquito, suggesting the existence of novel cuticular resistance mechanisms in this major disease vector.

Proteomic cardiovascular risk assessment in chronic kidney disease

AIMS

Chronic kidney disease (CKD) is widely prevalent and independently increases cardiovascular risk. Cardiovascular risk prediction tools derived in the general population perform poorly in CKD. Through large-scale proteomics discovery, this study aimed to create more accurate cardiovascular risk models.

METHODS AND RESULTS

Elastic net regression was used to derive a proteomic risk model for incident cardiovascular risk in 2182 participants from the Chronic Renal Insufficiency Cohort. The model was then validated in 485 participants from the Atherosclerosis Risk in Communities cohort. All participants had CKD and no history of cardiovascular disease at study baseline when ∼5000 proteins were measured. The proteomic risk model, which consisted of 32 proteins, was superior to both the 2013 ACC/AHA Pooled Cohort Equation and a modified Pooled Cohort Equation that included estimated glomerular filtrate rate. The Chronic Renal Insufficiency Cohort internal validation set demonstrated annualized receiver operating characteristic area under the curve values from 1 to 10 years ranging between 0.84 and 0.89 for the protein and 0.70 and 0.73 for the clinical models. Similar findings were observed in the Atherosclerosis Risk in Communities validation cohort. For nearly half of the individual proteins independently associated with cardiovascular risk, Mendelian randomization suggested a causal link to cardiovascular events or risk factors. Pathway analyses revealed enrichment of proteins involved in immunologic function, vascular and neuronal development, and hepatic fibrosis.

CONCLUSION

In two sizeable populations with CKD, a proteomic risk model for incident cardiovascular disease surpassed clinical risk models recommended in clinical practice, even after including estimated glomerular filtration rate. New biological insights may prioritize the development of therapeutic strategies for cardiovascular risk reduction in the CKD population.

Relationships Between Patient Race and Residential Race Context With Missed Human Immunodeficiency Virus Care Visits in the United States, 2010-2015

BACKGROUND

Racial inequities exist in retention in human immunodeficiency virus (HIV) care and multilevel analyses are needed to contextualize and address these differences. Leveraging data from a multisite clinical cohort of people with HIV (PWH), we assessed the relationships between patient race and residential characteristics with missed HIV care visits.

METHODS

Medical record and patient-reported outcome (PRO; including mental health and substance-use measures) data were drawn from 7 participating Center for AIDS Research Network of Integrated Clinical Systems (CNICS) sites including N = 20 807 PWH from January 2010 through December 2015. Generalized estimating equations were used to account for nesting within individuals and within census tracts in multivariable models assessing the relationship between race and missed HIV care visits, controlling for individual demographic and health characteristics and census tract characteristics.

RESULTS

Black PWH resided in more disadvantaged census tracts, on average. Black PWH residing in census tracts with higher proportion of Black residents were more likely to miss an HIV care visit. Non-Black PWH were less likely to miss a visit regardless of where they lived. These relationships were attenuated when PRO data were included.

CONCLUSIONS

Residential racial segregation and disadvantage may create inequities between Black PWH and non-Black PWH in retention in HIV care. Multilevel approaches are needed to retain PWH in HIV care, accounting for community, healthcare setting, and individual needs and resources.

Genome-wide analyses characterize shared heritability among cancers and identify novel cancer susceptibility regions

BACKGROUND

The shared inherited genetic contribution to risk of different cancers is not fully known. In this study, we leverage results from 12 cancer genome-wide association studies (GWAS) to quantify pairwise genome-wide genetic correlations across cancers and identify novel cancer susceptibility loci.

METHODS

We collected GWAS summary statistics for 12 solid cancers based on 376 759 participants with cancer and 532 864 participants without cancer of European ancestry. The included cancer types were breast, colorectal, endometrial, esophageal, glioma, head and neck, lung, melanoma, ovarian, pancreatic, prostate, and renal cancers. We conducted cross-cancer GWAS and transcriptome-wide association studies to discover novel cancer susceptibility loci. Finally, we assessed the extent of variant-specific pleiotropy among cancers at known and newly identified cancer susceptibility loci.

RESULTS

We observed widespread but modest genome-wide genetic correlations across cancers. In cross-cancer GWAS and transcriptome-wide association studies, we identified 15 novel cancer susceptibility loci. Additionally, we identified multiple variants at 77 distinct loci with strong evidence of being associated with at least 2 cancer types by testing for pleiotropy at known cancer susceptibility loci.

CONCLUSIONS

Overall, these results suggest that some genetic risk variants are shared among cancers, though much of cancer heritability is cancer-specific and thus tissue-specific. The increase in statistical power associated with larger sample sizes in cross-disease analysis allows for the identification of novel susceptibility regions. Future studies incorporating data on multiple cancer types are likely to identify additional regions associated with the risk of multiple cancer types.

A single N-terminal amino acid determines the distinct roles of histones H3 and H3.3 in the Drosophila male germline stem cell lineage

Adult stem cells undergo asymmetric cell divisions to produce 2 daughter cells with distinct cell fates: one capable of self-renewal and the other committed for differentiation. Misregulation of this delicate balance can lead to cancer and tissue degeneration. During asymmetric division of Drosophila male germline stem cells (GSCs), preexisting (old) and newly synthesized histone H3 are differentially segregated, whereas old and new histone variant H3.3 are more equally inherited. However, what underlies these distinct inheritance patterns remains unknown. Here, we report that the N-terminal tails of H3 and H3.3 are critical for their inheritance patterns, as well as GSC maintenance and proper differentiation. H3 and H3.3 differ at the 31st position in their N-termini with Alanine for H3 and Serine for H3.3. By swapping these 2 amino acids, we generated 2 mutant histones (i.e., H3A31S and H3.3S31A). Upon expressing them in the early-stage germline, we identified opposing phenotypes: overpopulation of early-stage germ cells in the H3A31S-expressing testes and significant germ cell loss in testes expressing the H3.3S31A. Asymmetric H3 inheritance is disrupted in the H3A31S-expressing GSCs, due to misincorporation of old histones between sister chromatids during DNA replication. Furthermore, H3.3S31A mutation accelerates old histone turnover in the GSCs. Finally, using a modified Chromatin Immunocleavage assay on early-stage germ cells, we found that H3A31S has enhanced occupancy at promoters and transcription starting sites compared with H3, while H3.3S31A is more enriched at transcriptionally silent intergenic regions compared to H3.3. Overall, these results suggest that the 31st amino acids for both H3 and H3.3 are critical for their proper genomic occupancy and function. Together, our findings indicate a critical role for the different amino acid composition of the N-terminal tails between H3 and H3.3 in an endogenous stem cell lineage and provide insights into the importance of proper histone inheritance in specifying cell fates and regulating cellular differentiation.

Severe Acute Respiratory Syndrome Coronavirus 2 Neutralizing Antibody Responses After Community Infections in Children and Adults

Background

We compared postinfection severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibody (nAb) responses among children and adults while the D614G-like strain and Alpha, Iota, and Delta variants circulated.

Methods

During August 2020-October 2021, households with adults and children were enrolled and followed in Utah, New York City, and Maryland. Participants collected weekly respiratory swabs that were tested for SARS-CoV-2 and had sera collected during enrollment and follow-up. Sera were tested for SARS-CoV-2 nAb by pseudovirus assay. Postinfection titers were characterized with biexponential decay models.

Results

Eighty participants had SARS-CoV-2 infection during the study (47 with D614G-like virus, 17 with B.1.1.7, and 8 each with B.1.617.2 and B.1.526 virus). Homologous nAb geometric mean titers (GMTs) trended higher in adults (GMT = 2320) versus children 0-4 (GMT = 425, P = .33) and 5-17 years (GMT = 396, P = .31) at 1-5 weeks postinfection but were similar from 6 weeks. Timing of peak titers was similar by age. Results were consistent when participants with self-reported infection before enrollment were included (n = 178).

Conclusions

The SARS-CoV-2 nAb titers differed in children compared to adults early after infection but were similar by 6 weeks postinfection. If postvaccination nAb kinetics have similar trends, vaccine immunobridging studies may need to compare nAb responses in adults and children 6 weeks or more after vaccination.

Characterizing SARS-CoV-2 Transcription of Subgenomic and Genomic RNAs During Early Human Infection Using Multiplexed Droplet Digital Polymerase Chain Reaction

BACKGROUND

Control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission requires understanding SARS-CoV-2 replication dynamics.

METHODS

We developed a multiplexed droplet digital polymerase chain reaction (ddPCR) assay to quantify SARS-CoV-2 subgenomic RNAs (sgRNAs), which are only produced during active viral replication, and discriminate them from genomic RNAs (gRNAs). We applied the assay to specimens from 144 people with single nasopharyngeal samples and 27 people with >1 sample. Results were compared to quantitative PCR (qPCR) and viral culture.

RESULTS

sgRNAs were quantifiable across a range of qPCR cycle threshold (Ct) values and correlated with Ct values. The ratio sgRNA:gRNA was stable across a wide range of Ct values, whereas adjusted amounts of N sgRNA to a human housekeeping gene declined with higher Ct values. Adjusted sgRNA and gRNA amounts were quantifiable in culture-negative samples, although levels were significantly lower than in culture-positive samples. Daily testing of 6 persons revealed that sgRNA is concordant with culture results during the first week of infection but may be discordant with culture later in infection. sgRNA:gRNA is constant during infection despite changes in viral culture.

CONCLUSIONS

Ct values from qPCR correlate with active viral replication. More work is needed to understand why some cultures are negative despite presence of sgRNA.

Designing robots that do no harm: understanding the challenges of Ethics for Robots

This article describes key challenges in creating an ethics "for" robots. Robot ethics is not only a matter of the effects caused by robotic systems or the uses to which they may be put, but also the ethical rules and principles that these systems ought to follow-what we call "Ethics for Robots." We suggest that the Principle of Nonmaleficence, or "do no harm," is one of the basic elements of an ethics for robots-especially robots that will be used in a healthcare setting. We argue, however, that the implementation of even this basic principle will raise significant challenges for robot designers. In addition to technical challenges, such as ensuring that robots are able to detect salient harms and dangers in the environment, designers will need to determine an appropriate sphere of responsibility for robots and to specify which of various types of harms must be avoided or prevented. These challenges are amplified by the fact that the robots we are currently able to design possess a form of semi-autonomy that differs from other more familiar semi-autonomous agents such as animals or young children. In short, robot designers must identify and overcome the key challenges of an ethics for robots before they may ethically utilize robots in practice.

Coronavirus Disease 2019-Associated Pulmonary Aspergillosis: A Noninvasive Screening Model for Additional Diagnostics

Background

Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) is likely underdiagnosed, and current diagnostic tools are either invasive or insensitive.

Methods

A retrospective study of mechanically ventilated patients with COVID-19 admitted to 5 Johns Hopkins hospitals between March 2020 and June 2021 was performed. Multivariable logistic regression was used for the CAPA prediction model building. Performance of the model was assessed using the area under the receiver operating characteristic curve (AUC).

Results

In the cohort of 832 patients, 98 (11.8%) met criteria for CAPA. Age, time since intubation, dexamethasone for COVID-19 treatment, underlying pulmonary circulatory diseases, human immunodeficiency virus, multiple myeloma, cancer, or hematologic malignancies were statistically significantly associated with CAPA and were included in the CAPA prediction model, which showed an AUC of 0.75 (95% confidence interval, .70-.80). At a screening cutoff of ≥0.085, it had a sensitivity of 82%, a specificity of 51%, a positive predictive value of 18.6%, and a negative predictive value of 95.3%. (The CAPA screening score calculator is available at www.transplantmodels.com).

Conclusions

We developed a CAPA risk score as a noninvasive tool to aid in CAPA screening for patients with severe COVID-19. Our score will also identify a group of patients who are unlikely to have CAPA and who therefore need not undergo additional diagnostics and/or empiric antifungal therapy.

Prospective associations of health literacy with clinical outcomes in adults with CKD: findings from the CRIC study

BACKGROUND

Limited health literacy is associated with significant morbidity and mortality in the general population but the relation of health literacy with long-term clinical outcomes among adults with chronic kidney disease (CKD) is less clear.

METHODS

Prospective data from the Chronic Renal Insufficiency Cohort (CRIC) Study (n = 3715) were used. Health literacy was assessed with the Short Test of Functional Health Literacy in Adults (dichotomized as limited/adequate). Cox proportional hazards models were used to separately examine the relations of health literacy with CKD progression, cardiovascular event (any of the following: myocardial infarction, congestive heart failure, stroke or peripheral artery disease), and all-cause, cardiovascular and non-cardiovascular mortality. Poisson regression was used to assess the health literacy-hospitalization association. Models were sequentially adjusted: Model 1 adjusted for potential confounders (sociodemographic factors), while Model 2 additionally adjusted for potential mediators (clinical and lifestyle factors) of the associations of interest.

RESULTS

In confounder-adjusted models, participants with limited (vs adequate) health literacy [555 (15%)] had an increased risk of CKD progression [hazard ratio (HR) 1.34; 95% confidence interval (CI) 1.06-1.71], cardiovascular event (HR 1.67; 95% CI 1.39-2.00), hospitalization (rate ratio 1.33; 95% CI 1.26-1.40), and all-cause (HR 1.54; 95% CI 1.27-1.86), cardiovascular (HR 2.39; 95% CI 1.69-3.38) and non-cardiovascular (HR 1.27; 95% CI 1.01-1.60) mortality. Additional adjustments for potential mediators (Model 2) showed similar results except that the relations of health literacy with CKD progression and non-cardiovascular mortality were no longer statistically significant.

CONCLUSIONS

In the CRIC Study, adults with limited (vs adequate) health literacy had a higher risk for CKD progression, cardiovascular event, hospitalization and mortality-regardless of adjustment for potential confounders.

Risk of relapse of ANCA-associated vasculitis among patients homozygous for the proteinase 3 gene Val119Ile polymorphism

BACKGROUND

The frequency of proteinase 3 gene (PRTN3) polymorphisms in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is not fully characterised. We hypothesise that the presence of a PRTN3 gene polymorphism (single nucleotide polymorphism (SNP) rs351111) is relevant for clinical outcomes.

METHODS

DNA variant calling for SNP rs351111 (chr.19:844020, c.355G>A) in PRTN3 gene assessed the allelic frequency in patients with PR3-AAV included in the Rituximab in ANCA-Associated Vasculitis trial. This was followed by RNA-seq variant calling to characterise the mRNA expression. We compared clinical outcomes between patients homozygous for PRTN3-Ile119 or PRTN3-Val119.

RESULTS

Whole blood samples for DNA calling were available in 188 patients. 75 patients with PR3-AAV had the allelic variant: 62 heterozygous PRTN3-Val119Ile and 13 homozygous for PRTN3-Ile119. RNA-seq was available for 89 patients and mRNA corresponding to the allelic variant was found in 32 patients with PR3-AAV: 25 heterozygous PRTN3-Val119Ile and 7 homozygous for PRTN3-Ile119. The agreement between the DNA calling results and mRNA expression of the 86 patients analysed by both methods was 100%. We compared the clinical outcomes of 64 patients with PR3-AAV: 51 homozygous for PRTN3-Val119 and 13 homozygous for PRTN3-Ile119. The frequency of severe flares at 18 months in homozygous PRTN3-Ile119 was significantly higher when compared with homozygous PRTN3-Val119 (46.2% vs 19.6%, p=0.048). Multivariate analysis identified homozygous PR3-Ile119 as main predictor of severe relapse (HR 4.67, 95% CI 1.16 to 18.86, p=0.030).

CONCLUSION

In patients with PR3-AAV, homozygosity for PRTN3-Val119Ile polymorphism appears associated with higher frequency of severe relapse. Further studies are necessary to better understand the association of this observation with the risk of severe relapse.

SARS-CoV-2 Infection and Testing Experiences in a Nationwide Sample of Transgender and Gender-Diverse Adults, June-December 2021

OBJECTIVES

COVID-19 surveillance data are rarely collected or disaggregated by gender identity in the United States. We quantified COVID-19 testing experiences and SARS-CoV-2 infection history among transgender and gender-diverse (TGD) people to inform testing strategies and public health responses.

METHODS

From June 14 through December 16, 2021, TGD adults enrolled in a US nationwide online survey with optional SARS-CoV-2 antibody testing. We used multinomial regression analyses to identify correlates of suspected and confirmed SARS-CoV-2 infection (vs no known infection). We identified correlates of inability to access COVID-19 testing when needed using generalized linear models for binomial variables.

RESULTS

Participants (N = 2092) reported trans masculine (30.5%), trans feminine (27.3%), and nonbinary (42.2%) gender identities. Ten percent of respondents had a confirmed history of SARS-CoV-2 infection, and 29.8% had a history of suspected SARS-CoV-2 infection. Nonbinary gender (adjusted prevalence ratio [aPR] = 1.68; 95% CI, 1.12-2.53), experiencing homelessness (aPR = 1.65; 95% CI, 1.05-2.60), and food insecurity (aPR = 1.45; 95% CI, 1.03-2.04) were associated with confirmed SARS-CoV-2 infection. Food insecurity (aPR = 1.38; 95% CI, 1.10-1.72), chronic physical health condition (aPR = 1.44; 95% CI, 1.15-1.80), chronic mental health condition (aPR = 3.65; 95% CI, 2.40-5.56), and increased anticipated discrimination scores (aPR = 1.03; 95% CI, 1.01-1.05) were associated with suspected SARS-CoV-2 infection. Thirty-four percent (n = 694 of 2024) of participants reported an inability to access COVID-19 testing when needed, which was associated with Latinx or Hispanic ethnicity, inconsistent telephone access, homelessness, disability, and transportation limitations. The majority (79.4%) reported a complete COVID-19 vaccine course at the time of participation.

CONCLUSIONS

Inclusion of TGD people in public health surveillance and tailored public health strategies to address TGD communities' social and structural vulnerabilities may reduce barriers to COVID-19 testing.

From Molecular to Multiasperity Contacts: How Roughness Bridges the Friction Scale Gap

The tangential force required to observe slip across a whole frictional interface can increase over time under a constant load, due to any combination of creep, chemical, or structural changes of the interface. In macroscopic rate-and-state models, these frictional aging processes are lumped into an ad hoc state variable. Here we explain, for a frictional system exclusively undergoing structural aging, how the macroscopic friction response emerges from the interplay between the surface roughness and the molecular motion within adsorbed monolayers. The existence of contact junctions and their friction dynamics are studied through coupled experimental and computational approaches. The former provides detailed measurements of how the friction force decays, after the stiction peak, to a steady-state value over a few nanometers of sliding distance, while the latter demonstrates how this memory distance is related to the evolution of the number of cross-surface attractive physical links, within contact junctions, between the molecules adsorbed on the rough surfaces. We also show that roughness is a sufficient condition for the appearance of structural aging. Using a unified model for friction between rough adsorbed monolayers, we show how contact junctions are a key component in structural aging and how the infrajunction molecular motion can control the macroscopic response.

The adult Drosophila testis lacks a mechanism to replenish missing niche cells

The adult Drosophila testis contains a well-defined niche created by a cluster of hub cells, which secrete signals that maintain adjacent germline stem cells and somatic cyst stem cells (CySCs). Hub cells are normally quiescent in adult flies but can exit quiescence, delaminate from the hub and convert into CySCs after ablation of all CySCs. The opposite event, CySC conversion into hub cells, was proposed to occur under physiological conditions, but the frequency of this event is debated. Here, to probe further the question of whether or not hub cells can be regenerated, we developed methods to genetically ablate some or all hub cells. Surprisingly, when flies were allowed to recover from ablation, the missing hub cells were not replaced. Hub cells did not exit quiescence after partial ablation of hub cells, and labeled cells from outside the hub did not enter the hub during or after ablation. Despite its ability to exit quiescence in response to CySC ablation, we conclude that the hub in the adult Drosophila testis does not have a mechanism to replenish missing hub cells.

Senescent stroma induces nuclear deformations in cancer cells via the inhibition of RhoA/ROCK/myosin II-based cytoskeletal tension

The presence of senescent cells within tissues has been functionally linked to malignant transformations. Here, using tension-gauge tethers technology, particle-tracking microrheology, and quantitative microscopy, we demonstrate that senescent-associated secretory phenotype (SASP) derived from senescent fibroblasts impose nuclear lobulations and volume shrinkage on malignant cells, which stems from the loss of RhoA/ROCK/myosin II-based cortical tension. This loss in cytoskeletal tension induces decreased cellular contractility, adhesion, and increased mechanical compliance. These SASP-induced morphological changes are, in part, mediated by Lamin A/C. These findings suggest that SASP induces defective outside-in mechanotransduction from actomyosin fibers in the cytoplasm to the nuclear lamina, thereby triggering a cascade of biophysical and biomolecular changes in cells that associate with malignant transformations.

A Scoping Review on Resources, Tools, and Programs to Support Women's Leadership in Global Health: What Is Available, What Works, and How Do We Know?

Background

The unequal representation of women in global health leadership is a prevalent issue laterally across global health fields and vertically down experience levels. Although women compose much of the workforce, gender-based barriers prevent female talent from filling their appropriate leadership roles, which funnels unique expertise and problem-solving skills on a diversity of health topics out of positions of leadership. Currently, many calls to action have been proposed to raise awareness of the lack of women's global health leadership, with Women in Global Health as one of the more prominent movements. This paper evaluates how the priorities and strategies for leadership training and development set forth by such movements have changed the landscape of available programs and resources for women in global health, based on availability, success, and evaluation.

Objectives

This manuscript maps existing programs and resources that support women's leadership in global health and describes available evaluations and documented outcomes.

Methods

We used a dual approach of a peer-reviewed and gray literature search to build a comprehensive list of existing programs and resources designed to support women's leadership in global health. Out of 54 items included for full-text review and 22 gray literature items screened for inclusion, a total of 31 resources were processed in the final extraction. We used descriptive quantitative analysis for categorical and binary variables, while qualitative data from evaluations were analyzed for outcomes.

Findings

Resources were in the form of conferences, supplemental resources to conferences, certificate programs, coursework, stand-alone documents, single-focus programs, and mostly multicomponent programs. Most resources did not have a global health focus area, and a third of the total resources identified women first authors from predominantly high-income countries. About half of the resources mention mentorship and networking as activities incorporated as part of the resource. Over half of the resources did not have a target audience, and most resources were free to users.While there is a lack of consistent and meaningful evaluation of the resources, the available captured metrics of success were described as the number of career-advancing opportunities after using the resources. Examples of opportunities include enrollment in graduate school, receiving academic promotions, participating in internships, presenting at conferences, and publications.

Conclusion

While the supply of existing programming and resources to advance women's leadership in the global health field is limited in terms of quantity, it is rich in diverse formats, content, and implementation. This scoping review supports the notion that empowered female leadership in global health requires a complementary support system that encourages the unique needs and talents of female leaders. Such a support system needs inclusive targeting regardless of experience level, academic degree, or location. Furthermore, evaluations of resources will be critical in maintaining meaningful interventions that effectively dismantle the infrastructures that continue to limit the success of women leaders in global health.

The D614G mutation redirects SARS-CoV-2 spike to lysosomes and suppresses deleterious traits of the furin cleavage site insertion mutation

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) egress occurs by lysosomal exocytosis. We show that the Spike D614G mutation enhances Spike trafficking to lysosomes, drives Spike-mediated reprogramming of lysosomes, and reduces cell surface Spike expression by ~3-fold. D614G is not a human-specific adaptation. Rather, it is an adaptation to the earlier furin cleavage site insertion (FCSI) mutation that occurred at the genesis of SARS-CoV-2. While advantageous to the virus, furin cleavage of spike has deleterious effects on spike structure and function, inhibiting its trafficking to lysosomes and impairing its infectivity by the transmembrane serine protease 2(TMPRSS2)-independent, endolysosomal pathway. D614G restores spike trafficking to lysosomes and enhances the earliest events in SARS-CoV-2 infectivity, while spike mutations that restore SARS-CoV-2's TMPRSS2-independent infectivity restore spike's trafficking to lysosomes. Together, these and other results show that D614G is an intragenic suppressor of deleterious traits linked to the FCSI and lend additional support to the endolysosomal model of SARS-CoV-2 egress and entry.

Alpha-T-catenin is expressed in peripheral nerves as a constituent of Schwann cell adherens junctions

The adherens junction component, alpha-T-catenin (αTcat) is an established contributor to cardiomyocyte junction structure and function, but recent genomic studies link CTNNA3 polymorphisms to diseases with no clear cardiac underpinning, including asthma, autism and multiple sclerosis, suggesting causal contributions from a different cell-type. We show Ctnna3 mRNA is highly expressed in peripheral nerves (e.g. vagus and sciatic), where αTcat protein enriches at paranodes and myelin incisure adherens junctions of Schwann cells. We validate αTcat immunodetection specificity using a new Ctnna3-knock-out fluorescence reporter mouse line yet find no obvious Schwann cell loss-of-function morphology at the light microscopic level. CTNNA3/Ctnna3 mRNA is also abundantly detected in oligodendrocytes of the central nervous system via public databases, supporting a general role for αTcat in these unique cell-cell junctions. These data suggest that the wide range of diseases linked to CTNNA3 may be through its role in maintaining neuroglial functions of central and peripheral nervous systems. This article has a corresponding First Person interview with the co-first authors of the paper.

A qualitative study of factors resulting in care delays for adults with meningitis in Zambia

BACKGROUND

Meningitis causes significant mortality in regions with high comorbid HIV and TB. Improved outcomes are hindered by limited understanding of factors that delay adequate care.

METHODS

In-depth interviews of patients admitted to the University Teaching Hospital with suspected meningitis, their caregivers, doctors and nurses were conducted. Patient/caregiver interviews explored meningitis understanding, treatment prior to admission and experiences since admission. Provider interviews addressed current and prior experiences with meningitis patients and hospital barriers to care. A conceptual framework based on the Three Delays Model identified factors that delayed care.

RESULTS

Twenty-six patient/caregiver, eight doctor and eight nurse interviews occurred. Four delays were identified: in-home care; transportation to a health facility; clinic/first-level hospital care; and third-level hospital. Overcrowding and costly diagnostic testing delayed outpatient care; 23% of patients began with treatment inside the home due to prior negative experiences with biomedical care. Admission occurred after multiple clinic visits, where subsequent delays occurred during testing and treatment.

CONCLUSIONS

Delays in care from home to hospital impair quality meningitis care in Zambia. Interventions to improve outcomes must address patient, community and health systems factors. Patient/caregiver education regarding signs of meningitis and indications for care-seeking are warranted to reduce treatment delays.