Single-cell chromatin accessibility reveals malignant regulatory programs in primary human cancers.

To identify cancer-associated gene regulatory changes, we generated single-cell chromatin accessibility landscapes across eight tumor types as part of The Cancer Genome Atlas. Tumor chromatin accessibility is strongly influenced by copy number alterations that can be used to identify subclones, yet underlying cis-regulatory landscapes retain cancer type-specific features. Using organ-matched healthy tissues, we identified the "nearest healthy" cell types in diverse cancers, demonstrating that the chromatin signature of basal-like-subtype breast cancer is most similar to secretory-type luminal epithelial cells. Neural network models trained to learn regulatory programs in cancer revealed enrichment of model-prioritized somatic noncoding mutations near cancer-associated genes, suggesting that dispersed, nonrecurrent, noncoding mutations in cancer are functional. Overall, these data and interpretable gene regulatory models for cancer and healthy tissue provide a framework for understanding cancer-specific gene regulation.

Disparate pathways for extrachromosomal DNA biogenesis and genomic DNA repair.

Oncogene amplification on extrachromosomal DNA (ecDNA) is a pervasive driver event in cancer, yet our understanding of how ecDNA forms is limited. Here, we couple a CRISPR-based method for ecDNA induction with extensive characterization of newly formed ecDNA to examine their biogenesis. We find that DNA circularization is efficient, irrespective of 3D genome context, with formation of 800kb, 1 Mb, and 1.8 Mb ecDNAs reaching or exceeding 15%. We show non-homologous end joining and microhomology-mediated end joining both contribute to ecDNA formation, while inhibition of DNA-PKcs and ATM have opposing impacts on ecDNA formation. EcDNA and the corresponding chromosomal excision scar can form at significantly different rates and respond differently to DNA-PKcs and ATM inhibition. Taken together, our results support a model of ecDNA formation in which double strand break ends dissociate from their legitimate ligation partners prior to joining of illegitimate ends to form the ecDNA and excision scar.

Associations between exposure to extreme ambient heat and neural tube defects in Georgia, USA: A population-based case-control study.

INTRODUCTION: The association between extreme ambient heat exposures during pregnancy and neural tube defects (NTDs) in offspring remains unclear. This study sought to estimate the association between exposure to extreme ambient heat during periconception and NTDs. METHODS: This population-based case-control study in Georgia, USA (1994-2017) included 825 isolated NTD cases (473 anencephaly, 352 spina bifida) and 3,300 controls matched 1:4 on county of residence and time period of delivery. Daily ambient temperature data were linked to fetal death and birth records by county of residence. Extreme ambient heat exposure was defined as the number of consecutive days the daily apparent temperature exceeded the county-specific 95th percentile (derived over 1980-2010) during an eight-week periconception period. We calculated adjusted odds ratios (aORs) and 95% confidence intervals (CI) using conditional logistic regression models adjusted for maternal age, education, and ethnicity and month and year of last menstrual period. RESULTS: The aORs for NTDs were 1.09 (95% CI 1.01, 1.17), 1.18 (95% CI 1.03, 1.36), and 1.29 (95% CI 1.04, 1.58) for exposure to 1-2, 3-5, and 6 or more consecutive days with apparent ambient temperatures exceeding the county-specific 95th percentile during periconception, respectively, compared to no days of extreme ambient heat exposure. Weekly analysis of extreme heat exposure indicated consistently elevated odds of offspring NTDs during periconception. These results were largely driven by spina bifida cases. CONCLUSIONS: Our results highlight potential health threats posed by increasing global average temperatures for pregnant people with implications for increased risk of neural tube defects in their offspring.

Prenatal and Early Life Exposure to Ambient Air Pollutants Is Associated with the Fecal Metabolome in the First Two Years of Life.

Prenatal and early life air pollution exposure has been linked with several adverse health outcomes. However, the mechanisms underlying these relationships are not yet fully understood. Therefore, this study utilizes fecal metabolomics to determine if pre- and postnatal exposure to ambient air pollutants (i.e., PM10, PM2.5, and NO2) is associated with the fecal metabolome in the first 2 years of life in a Latino cohort from Southern California. The aims of this analysis were to estimate associations between (1) prenatal air pollution exposure with fecal metabolic features at 1-month of age, (2) prior month postnatal air pollution exposure with fecal metabolites from 1-month to 2 years of age, and (3) how postnatal air pollution exposure impacts the change over time of fecal metabolites in the first 2 years of life. Prenatal exposure to air pollutants was associated with several Level-1 metabolites, including those involved in vitamin B6 and tyrosine metabolism. Prior month air pollution exposure in the postnatal period was associated with Level-1 metabolites involved in histidine metabolism. Lastly, we found that pre- and postnatal ambient air pollution exposure was associated with changes in metabolic features involved in metabolic pathways including amino acid metabolism, histidine metabolism, and fatty acid metabolism.

Dual Use of Cannabis with Tobacco Is Associated with Increased Sugary Food and Drink Intake in Young People.

Rates of cannabis initiation among teenagers and young adults are increasing. Further, the use of various forms of cannabis (smoked or vaped) with nicotine (dual use) is increasingly common among young people. The health effects of dual use are lesser known, particularly in the context of high-potency cannabis products and across different routes of administration, which is ominous in terms of predicting future health outcomes. There is a long history of cannabis use being associated with decreased activity and increased snacking, both of which could portend an increased risk of metabolic and cardiovascular disease, particularly when these habits begin during formative years. However, modern forms of cannabis may not have these same effects. Here, we assess whether cannabis use alone and dual use of cannabis with nicotine impact dietary and exercise habits in young people. An anonymous, social media-based survey was designed based on the UC San Diego Inhalant Questionnaire and published diet and exercise questionnaires. A total of 457 surveys were completed. Young sole cannabis users represented 29% of responders, 16% were dual users of cannabis and nicotine, and 55% were non-users of either drug. Although the sole use of cannabis was not associated with dietary or activity differences relative to non-users, dual users of cannabis and nicotine reported higher consumption of unhealthy sugars. This novel finding of dual use being associated with increased sugar intake in young people raises concerns for an increased risk of metabolic syndrome and cardiovascular disease in this population.

CoRAL accurately resolves extrachromosomal DNA genome structures with long-read sequencing.

Extrachromosomal DNA (ecDNA) is a central mechanism for focal oncogene amplification in cancer, occurring in approximately 15% of early-stage cancers and 30% of late-stage cancers. EcDNAs drive tumor formation, evolution, and drug resistance by dynamically modulating oncogene copy-number and rewiring gene-regulatory networks. Elucidating the genomic architecture of ecDNA amplifications is critical for understanding tumor pathology and developing more effective therapies. Paired-end short-read (Illumina) sequencing and mapping have been utilized to represent ecDNA amplifications using a breakpoint graph, where the inferred architecture of ecDNA is encoded as a cycle in the graph. Traversals of breakpoint graph have been used to successfully predict ecDNA presence in cancer samples. However, short-read technologies are intrinsically limited in the identification of breakpoints, phasing together of complex rearrangements and internal duplications, and deconvolution of cell-to-cell heterogeneity of ecDNA structures. Long-read technologies, such as from Oxford Nanopore Technologies, have the potential to improve inference as the longer reads are better at mapping structural variants and are more likely to span rearranged or duplicated regions. Here, we propose CoRAL (Complete Reconstruction of Amplifications with Long reads), for reconstructing ecDNA architectures using long-read data. CoRAL reconstructs likely cyclic architectures using quadratic programming that simultaneously optimizes parsimony of reconstruction, explained copy number, and consistency of long-read mapping. CoRAL substantially improves reconstructions in extensive simulations and 10 datasets from previously-characterized cell lines as compared to previous short and long-read based tools. As long-read usage becomes wide-spread, we anticipate that CoRAL will be a valuable tool for profiling the landscape and evolution of focal amplifications in tumors.

Dust storms and cardiorespiratory emergency department visits in three Southwestern United States: application of a monitoring-based exposure metric.

Climate change is projected to increase the risk of dust storms, particularly in subtropical dryland, including the southwestern US. Research on dust storm's health impacts in the US is limited and hindered by challenges in dust storm identification. This study assesses the potential link between dust storms and cardiorespiratory emergency department (ED) visits in the southwestern US. We acquired data for 2005-2016 from eight IMPROVE (Interagency Monitoring of PROtected Visual Environments) sites in Arizona, California, and Utah. We applied a validated algorithm to identify dust storm days at each site. We acquired patient-level ED visit data from state agencies and ascertained visits for respiratory, cardiovascular, and cause-specific subgroups among patients residing in ZIP codes within 50 km of an IMPROVE site. Using a case-crossover design, we estimated short-term associations of ED visits and dust storms, controlling for temporally varying covariates. During 2005-2016, 40 dust storm days occurred at the eight IMPROVE sites. Mean PM10 and PM2.5 levels were three to six times greater on dust storm days compared to non-dust storm days. Over the study period, there were 2 524 259 respiratory and 2 805 925 cardiovascular ED visits. At lags of 1, 2, and 3 days after a dust storm, we observed 3.7% (95% CI: 1.0%, 7.6%), 4.9% (95% CI: 1.1%, 8.9%), and 5.0% (95% CI: 1.3%, 8.9%) elevated odds of respiratory ED visits compared to non-dust storm days. Estimated associations of dust storm days and cardiovascular disease ED visits were largely consistent with the null. Using a monitoring-based exposure metric, we observed associations among dust storms and respiratory ED visits. The results add to growing evidence of the health threat posed by dust storms. The dust storm metric was limited by lack of daily data; future research should consider information from satellite and numerical models to enhance dust storm characterization.

Clonal inactivation of TERT impairs stem cell competition.

Telomerase is intimately associated with stem cells and cancer, because it catalytically elongates telomeres-nucleoprotein caps that protect chromosome ends1. Overexpression of telomerase reverse transcriptase (TERT) enhances the proliferation of cells in a telomere-independent manner2-8, but so far, loss-of-function studies have provided no evidence that TERT has a direct role in stem cell function. In many tissues, homeostasis is shaped by stem cell competition, a process in which stem cells compete on the basis of inherent fitness. Here we show that conditional deletion of Tert in the spermatogonial stem cell (SSC)-containing population in mice markedly impairs competitive clone formation. Using lineage tracing from the Tert locus, we find that TERT-expressing SSCs yield long-lived clones, but that clonal inactivation of TERT promotes stem cell differentiation and a genome-wide reduction in open chromatin. This role for TERT in competitive clone formation occurs independently of both its reverse transcriptase activity and the canonical telomerase complex. Inactivation of TERT causes reduced activity of the MYC oncogene, and transgenic expression of MYC in the TERT-deleted pool of SSCs efficiently rescues clone formation. Together, these data reveal a catalytic-activity-independent requirement for TERT in enhancing stem cell competition, uncover a genetic connection between TERT and MYC and suggest that a selective advantage for stem cells with high levels of TERT contributes to telomere elongation in the male germline during homeostasis and ageing.

Cohesin prevents cross-domain gene coactivation.

The contrast between the disruption of genome topology after cohesin loss and the lack of downstream gene expression changes instigates intense debates regarding the structure-function relationship between genome and gene regulation. Here, by analyzing transcriptome and chromatin accessibility at the single-cell level, we discover that, instead of dictating population-wide gene expression levels, cohesin supplies a general function to neutralize stochastic coexpression tendencies of cis-linked genes in single cells. Notably, cohesin loss induces widespread gene coactivation and chromatin co-opening tens of million bases apart in cis. Spatial genome and protein imaging reveals that cohesin prevents gene co-bursting along the chromosome and blocks spatial mixing of transcriptional hubs. Single-molecule imaging shows that cohesin confines the exploration of diverse enhancer and core promoter binding transcriptional regulators. Together, these results support that cohesin arranges nuclear topology to control gene coexpression in single cells.

A human autoimmune organoid model reveals IL-7 function in coeliac disease.

In vitro models of autoimmunity are constrained by an inability to culture affected epithelium alongside the complex tissue-resident immune microenvironment. Coeliac disease (CeD) is an autoimmune disease in which dietary gluten-derived peptides bind to the major histocompatibility complex (MHC) class II human leukocyte antigen molecules (HLA)-DQ2 or HLA-DQ8 to initiate immune-mediated duodenal mucosal injury1-4. Here, we generated air-liquid interface (ALI) duodenal organoids from intact fragments of endoscopic biopsies that preserve epithelium alongside native mesenchyme and tissue-resident immune cells as a unit without requiring reconstitution. The immune diversity of ALI organoids spanned T cells, B and plasma cells, natural killer (NK) cells and myeloid cells, with extensive T-cell and B-cell receptor repertoires. HLA-DQ2.5-restricted gluten peptides selectively instigated epithelial destruction in HLA-DQ2.5-expressing organoids derived from CeD patients, and this was antagonized by blocking MHC-II or NKG2C/D. Gluten epitopes stimulated a CeD organoid immune network response in lymphoid and myeloid subsets alongside anti-transglutaminase 2 (TG2) autoantibody production. Functional studies in CeD organoids revealed that interleukin-7 (IL-7) is a gluten-inducible pathogenic modulator that regulates CD8+ T-cell NKG2C/D expression and is necessary and sufficient for epithelial destruction. Furthermore, endogenous IL-7 was markedly upregulated in patient biopsies from active CeD compared with remission disease from gluten-free diets, predominantly in lamina propria mesenchyme. By preserving the epithelium alongside diverse immune populations, this human in vitro CeD model recapitulates gluten-dependent pathology, enables mechanistic investigation and establishes a proof of principle for the organoid modelling of autoimmunity.

Association of household air pollution exposure and anemia among pregnant women: Analysis of baseline data from 'Household Air Pollution Intervention Network (HAPIN)' trial.

BACKGROUND: Anemia is common in low- and middle-income countries (LMICs), causing significant health issues and social burdens. Exposure to household air pollution from using biomass fuels for cooking and heating has been associated with anemia, but the exposure-response association has not been studied. OBJECTIVES: We evaluated the associations between personal exposure to air pollution and both hemoglobin levels and anemia prevalence among pregnant women in a multi-country randomized controlled trial. METHODS: We studied 3,163 pregnant women aged 18-35 years with 9-20 weeks of gestation, recruited as part of the Household Air Pollution Intervention Network (HAPIN) randomized controlled trial in Guatemala, India, Peru, and Rwanda. We assessed 24-hour personal exposures to fine particulate matter (PM2.5), black carbon (BC), and carbon monoxide (CO), and measured hemoglobin levels at baseline (15 ± 3 weeks gestation). Linear and logistic regression models were used to examine the associations of measured pollutants with hemoglobin levels and anemia prevalence, adjusting for confounding. RESULTS: Single-pollutant models showed associations of CO with higher hemoglobin levels and lower anemia prevalence. Bipollutant models involving CO and PM2.5 also revealed that an interquartile range (IQR) increase in CO concentrations (2.26 ppm) was associated with higher hemoglobin levels [ß = 0.04; 95 % confidence interval (CI): 0.01, 0.07], and a lower odds of anemia prevalence [odds ratios (OR) = 0.90; 95 % CI: 0.83, 0.98]. PM2.5 was inversely related to hemoglobin and positively associated with anemia, but results were not statistically significant at the 0.05 alpha level. County-specific results showed that 3 of 4 countries showed a similar association between CO and hemoglobin. We found no association of BC levels with hemoglobin levels or with anemia prevalence. CONCLUSION: Our findings suggest that exposure to CO is associated with higher hemoglobin and lower anemia prevalence among pregnant women, whereas PM2.5 showed the opposite associations.

Increasing access, equitability, and rigor in the assessment of Neighborhood Mortgage Discrimination.

Mortgage discrimination alters the distribution of investment, opportunity, and economic advantage-key contributors of health disparities. Leveraging Home Mortgage Disclosure Act data, we assessed mortgage denial risk in 380 U.S. urban areas. We estimated the risks by census tract-relative to the urban-specific average-using a Bayesian spatial model with conditionally autoregressive distributions fitted with integrated nested Laplace approximation. This approach borrows information through spatial and non-spatial smoothing, resulting in stable estimates in the presence of sparse data. The method, publicly accessible, allows researchers to apply our approach, fostering deeper insights into mortgage lending discrimination and systematic neighborhood disinvestment.

Transcriptional immune suppression and up-regulation of double-stranded DNA damage and repair repertoires in ecDNA-containing tumors.

Extrachromosomal DNA is a common cause of oncogene amplification in cancer. The non-chromosomal inheritance of ecDNA enables tumors to rapidly evolve, contributing to treatment resistance and poor outcome for patients. The transcriptional context in which ecDNAs arise and progress, including chromosomally-driven transcription, is incompletely understood. We examined gene expression patterns of 870 tumors of varied histological types, to identify transcriptional correlates of ecDNA. Here, we show that ecDNA-containing tumors impact four major biological processes. Specifically, ecDNA-containing tumors up-regulate DNA damage and repair, cell cycle control, and mitotic processes, but down-regulate global immune regulation pathways. Taken together, these results suggest profound alterations in gene regulation in ecDNA-containing tumors, shedding light on molecular processes that give rise to their development and progression.

Pathways for macrophage uptake of cell-free circular RNAs.

Circular RNAs (circRNAs) are stable RNAs present in cell-free RNA, which may comprise cellular debris and pathogen genomes. Here, we investigate the phenomenon and mechanism of cellular uptake and intracellular fate of exogenous circRNAs. Human myeloid cells and B cells selectively internalize extracellular circRNAs. Macrophage uptake of circRNA is rapid, energy dependent, and saturable. CircRNA uptake can lead to translation of encoded sequences and antigen presentation. The route of internalization influences immune activation after circRNA uptake, with distinct gene expression programs depending on the route of RNA delivery. Genome-scale CRISPR screens and chemical inhibitor studies nominate macrophage scavenger receptor MSR1, Toll-like receptors, and mTOR signaling as key regulators of receptor-mediated phagocytosis of circRNAs, a dominant pathway to internalize circRNAs in parallel to macropinocytosis. These results suggest that cell-free circRNA serves as an "eat me" signal and danger-associated molecular pattern, indicating orderly pathways of recognition and disposal.

hnRNPM protects against the dsRNA-mediated interferon response by repressing LINE-associated cryptic splicing.

RNA splicing is pivotal in post-transcriptional gene regulation, yet the exponential expansion of intron length in humans poses a challenge for accurate splicing. Here, we identify hnRNPM as an essential RNA-binding protein that suppresses cryptic splicing through binding to deep introns, maintaining human transcriptome integrity. Long interspersed nuclear elements (LINEs) in introns harbor numerous pseudo splice sites. hnRNPM preferentially binds at intronic LINEs to repress pseudo splice site usage for cryptic splicing. Remarkably, cryptic exons can generate long dsRNAs through base-pairing of inverted ALU transposable elements interspersed among LINEs and consequently trigger an interferon response, a well-known antiviral defense mechanism. Significantly, hnRNPM-deficient tumors show upregulated interferon-associated pathways and elevated immune cell infiltration. These findings unveil hnRNPM as a guardian of transcriptome integrity by repressing cryptic splicing and suggest that targeting hnRNPM in tumors may be used to trigger an inflammatory immune response, thereby boosting cancer surveillance.

Betrayal trauma and somatic symptoms among patients in a medically underserved primary care clinic.

OBJECTIVE: Betrayal Trauma Theory posits that victims of trauma are more prone to developing psychological and physical problems if the traumatic event includes the element of betrayal. We sought to evaluate the impact of betrayal trauma versus nonbetrayal trauma and no trauma exposure on the risk of patients' reporting somatic symptoms in six domains (gastrointestinal, cardiopulmonary, musculoskeletal, pseudoneurological, gynecological, or any symptom). METHOD: Medically underserved patients (N = 1,350) who presented to a primary care clinic in California completed a structured standardized interview that assessed trauma history (Diagnostic Interview Schedule) and somatization symptoms (Composite International Diagnostic Interview). Using Betrayal Trauma Theory as a guide, respondents were classified into "no trauma," "nonbetrayal trauma," and "betrayal trauma" groups. RESULTS: Compared to "no trauma" patients, patients who experienced nonbetrayal trauma were more likely to endorse all symptom domains (ORs = 1.30-1.50) except gastrointestinal and musculoskeletal; compared to "no trauma" patients, patients who experienced betrayal trauma were more likely to endorse all symptom domains (ORs = 1.61-3.12) except gynecological. Compared to patients who experienced nonbetrayal trauma, exposure to betrayal trauma increased the likelihood of reporting any (OR = 2.25), gastrointestinal (OR = 1.56), and pseudoneurological symptoms (OR = 1.71), as well as symptoms spanning multiple physiological systems (incidence rate ratio = 1.27). Each nonbetrayal trauma increased the likelihood of symptom reporting across all domains (ORs = 1.18-1.40); each betrayal trauma increased the likelihood across all domains (ORs = 1.41-2.31) except gynecological. CONCLUSION: Both nonbetrayal and betrayal trauma may predispose victims to somatization. Compared to nonbetrayal trauma, betrayal trauma confers a greater magnitude of risk for having a somatic symptom across each symptom domain except gynecological. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Preterm and Early-Term Delivery After Heat Waves in 50 US Metropolitan Areas.

Importance: Heat waves are increasing in frequency, intensity, and duration and may be acutely associated with pregnancy outcomes. Objective: To examine changes in daily rates of preterm and early-term birth after heat waves in a 25-year nationwide study. Design, Setting, and Participants: This cohort study of singleton births used birth records from 1993 to 2017 from the 50 most populous US metropolitan statistical areas (MSAs). The study included 53 million births, covering 52.8% of US births over the period. Data were analyzed between October 2022 and March 2023 at the National Center for Health Statistics. Exposures: Daily temperature data from Daymet at 1-km2 resolution were averaged over each MSA using population weighting. Heat waves were defined in the 4 days (lag, 0-3 days) or 7 days (lag, 0-6 days) preceding birth. Main Outcomes and Measures: Daily counts of preterm birth (28 to <37 weeks), early-term birth (37 to <39 weeks), and ongoing pregnancies in each gestational week on each day were enumerated in each MSA. Rate ratios for heat wave metrics were obtained from time-series models restricted to the warm season (May to September) adjusting for MSA, year, day of season, and day of week, and offset by pregnancies at risk. Results: There were 53 154 816 eligible births in the 50 MSAs from 1993 to 2017; 2 153 609 preterm births and 5 795 313 early-term births occurring in the warm season were analyzed. A total of 30.0% of mothers were younger than 25 years, 53.8% were 25 to 34 years, and 16.3% were 35 years or older. Heat waves were positively associated with daily rates of preterm and early-term births, showing a dose-response association with heat wave duration and temperatures and stronger associations in the more acute 4-day window. After 4 consecutive days of mean temperatures exceeding the local 97.5th percentile, the rate ratio for preterm birth was 1.02 (95% CI, 1.00-1.03), and the rate ratio for early-term birth was 1.01 (95% CI, 1.01-1.02). For the same exposure, among those who were 29 years of age or younger, had a high school education or less, and belonged to a racial or ethnic minority group, the rate ratios were 1.04 (95% CI, 1.02-1.06) for preterm birth and 1.03 (95% CI, 1.02-1.05) for early-term birth. Results were robust to alternative heat wave definitions, excluding medically induced deliveries, and alternative statistical model specifications. Conclusions and Relevance: In this cohort study, preterm and early-term birth rates increased after heat waves, particularly among socioeconomically disadvantaged subgroups. Extreme heat events have implications for perinatal health.

Impact of randomly assigned "pay-as-you-go" liquefied petroleum gas prices on energy use for cooking: Experimental pilot evidence from rural Rwanda.

The disease burden related to air pollution from traditional solid-fuel cooking practices in low- and middle-income countries impacts millions of people globally. Although the use of liquefied petroleum gas (LPG) fuel for cooking can meaningfully reduce household air pollution concentrations, major barriers, including affordability and accessibility, have limited widespread adoption. Using a randomized controlled trial, our objective was to evaluate the association between the cost and use of LPG among 23 rural Rwandan households. We provided a 2-burner LPG stove with accessories and incorporated a "pay-as-you-go" (PAYG) LPG service model that included fuel delivery. PAYG services remove the large up-front cost of cylinder refills by integrating "smart meter" technology that allows participants to pay in incremental amounts, as needed. We assigned three randomized discounted prices for LPG to each household at ~4-week intervals over a 12-week period. We modeled the relationship between randomized PAYG LPG price and use (standardized to monthly periods), analyzing effect modification by relative household wealth. A 1000 Rwandan Franc (about 1 USD at the time of the study) increase in LPG price/kg was associated with a 4.1 kg/month decrease in use (95% confidence interval [CI]: -6.7, -1.6; n=69 observations). Wealth modified this association; we observed a 9.7 kg/month reduction (95% CI: -14.8, -4.5) among wealthier households and a 2.5 kg/month reduction (95% CI: -5.3, 0.3) among lower-wealth households (p-interaction=0.01). The difference in price sensitivity was driven by higher LPG use among wealthier households at more heavily discounted prices; from an 80% to 10% discount, wealthy households used 17.5 to 5.3 kg/month and less wealthy households used 6.2 to 3.1 kg/month. Our pilot-level experimental evidence of PAYG LPG in a rural low-resource setting suggests that further exploration of subsidized pricing varied by household wealth is needed to ensure future policy initiatives can achieve targets without exacerbating inequities.

Organ- and Cell-Selective Delivery of mRNA In Vivo Using Guanidinylated Serinol Charge-Altering Releasable Transporters.

Selective RNA delivery is required for the broad implementation of RNA clinical applications, including prophylactic and therapeutic vaccinations, immunotherapies for cancer, and genome editing. Current polyanion delivery relies heavily on cationic amines, while cationic guanidinium systems have received limited attention due in part to their strong polyanion association, which impedes intracellular polyanion release. Here, we disclose a general solution to this problem in which cationic guanidinium groups are used to form stable RNA complexes upon formulation but at physiological pH undergo a novel charge-neutralization process, resulting in RNA release. This new delivery system consists of guanidinylated serinol moieties incorporated into a charge-altering releasable transporter (GSer-CARTs). Significantly, systematic variations in structure and formulation resulted in GSer-CARTs that exhibit highly selective mRNA delivery to the lung (∼97%) and spleen (∼98%) without targeting ligands. Illustrative of their breadth and translational potential, GSer-CARTs deliver circRNA, providing the basis for a cancer vaccination strategy, which in a murine model resulted in antigen-specific immune responses and effective suppression of established tumors.