Role of Microbiota-Derived Bile Acids in Enteric Infections.

In this issue of Cell, Alavi et al. report that infection by Vibrio cholerae is blocked by gut microbiome-mediated hydrolysis of bile acids. Cholera therefore joins amebic dysentery and Clostridioides difficile colitis as enteric infections profoundly influenced by the microbiome's impact on bile acid metabolism.

Widespread microRNA degradation elements in target mRNAs can assist the encoded proteins.

Binding of microRNAs (miRNAs) to mRNAs normally results in post-transcriptional repression of gene expression. However, extensive base-pairing between miRNAs and target RNAs can trigger miRNA degradation, a phenomenon called target RNA-directed miRNA degradation (TDMD). Here, we systematically analyzed Argonaute-CLASH (cross-linking, ligation, and sequencing of miRNA-target RNA hybrids) data and identified numerous candidate TDMD triggers, focusing on their ability to induce nontemplated nucleotide addition at the miRNA 3' end. When exogenously expressed in various cell lines, eight triggers induce degradation of corresponding miRNAs. Both the TDMD base-pairing and surrounding sequences are essential for TDMD. CRISPR knockout of endogenous trigger or ZSWIM8, a ubiquitin ligase essential for TDMD, reduced miRNA degradation. Furthermore, degradation of miR-221 and miR-222 by a trigger in BCL2L11, which encodes a proapoptotic protein, enhances apoptosis. Therefore, we uncovered widespread TDMD triggers in target RNAs and demonstrated an example that could functionally cooperate with the encoded protein.

Climate change increases cross-species viral transmission risk.

At least 10,000 virus species have the ability to infect humans but, at present, the vast majority are circulating silently in wild mammals1,2. However, changes in climate and land use will lead to opportunities for viral sharing among previously geographically isolated species of wildlife3,4. In some cases, this will facilitate zoonotic spillover-a mechanistic link between global environmental change and disease emergence. Here we simulate potential hotspots of future viral sharing, using a phylogeographical model of the mammal-virus network, and projections of geographical range shifts for 3,139 mammal species under climate-change and land-use scenarios for the year 2070. We predict that species will aggregate in new combinations at high elevations, in biodiversity hotspots, and in areas of high human population density in Asia and Africa, causing the cross-species transmission of their associated viruses an estimated 4,000 times. Owing to their unique dispersal ability, bats account for the majority of novel viral sharing and are likely to share viruses along evolutionary pathways that will facilitate future emergence in humans. Notably, we find that this ecological transition may already be underway, and holding warming under 2 °C within the twenty-first century will not reduce future viral sharing. Our findings highlight an urgent need to pair viral surveillance and discovery efforts with biodiversity surveys tracking the range shifts of species, especially in tropical regions that contain the most zoonoses and are experiencing rapid warming.

Mirvetuximab Soravtansine in FRα-Positive, Platinum-Resistant Ovarian Cancer.

BACKGROUND: Mirvetuximab soravtansine-gynx (MIRV), a first-in-class antibody-drug conjugate targeting folate receptor α (FRα), is approved for the treatment of platinum-resistant ovarian cancer in the United States. METHODS: We conducted a phase 3, global, confirmatory, open-label, randomized, controlled trial to compare the efficacy and safety of MIRV with the investigator's choice of chemotherapy in the treatment of platinum-resistant, high-grade serous ovarian cancer. Participants who had previously received one to three lines of therapy and had high FRα tumor expression (≥75% of cells with ≥2+ staining intensity) were randomly assigned in a 1:1 ratio to receive MIRV (6 mg per kilogram of adjusted ideal body weight every 3 weeks) or chemotherapy (paclitaxel, pegylated liposomal doxorubicin, or topotecan). The primary end point was investigator-assessed progression-free survival; key secondary analytic end points included objective response, overall survival, and participant-reported outcomes. RESULTS: A total of 453 participants underwent randomization; 227 were assigned to the MIRV group and 226 to the chemotherapy group. The median progression-free survival was 5.62 months (95% confidence interval [CI], 4.34 to 5.95) with MIRV and 3.98 months (95% CI, 2.86 to 4.47) with chemotherapy (P<0.001). An objective response occurred in 42.3% of the participants in the MIRV group and in 15.9% of those in the chemotherapy group (odds ratio, 3.81; 95% CI, 2.44 to 5.94; P<0.001). Overall survival was significantly longer with MIRV than with chemotherapy (median, 16.46 months vs. 12.75 months; hazard ratio for death, 0.67; 95% CI, 0.50 to 0.89; P = 0.005). During the treatment period, fewer adverse events of grade 3 or higher occurred with MIRV than with chemotherapy (41.7% vs. 54.1%), as did serious adverse events of any grade (23.9% vs. 32.9%) and events leading to discontinuation (9.2% vs. 15.9%). CONCLUSIONS: Among participants with platinum-resistant, FRα-positive ovarian cancer, treatment with MIRV showed a significant benefit over chemotherapy with respect to progression-free and overall survival and objective response. (Funded by ImmunoGen; MIRASOL ClinicalTrials.gov number, NCT04209855.).

Multi-layered maps of neuropil with segmentation-guided contrastive learning.

Maps of the nervous system that identify individual cells along with their type, subcellular components and connectivity have the potential to elucidate fundamental organizational principles of neural circuits. Nanometer-resolution imaging of brain tissue provides the necessary raw data, but inferring cellular and subcellular annotation layers is challenging. We present segmentation-guided contrastive learning of representations (SegCLR), a self-supervised machine learning technique that produces representations of cells directly from 3D imagery and segmentations. When applied to volumes of human and mouse cortex, SegCLR enables accurate classification of cellular subcompartments and achieves performance equivalent to a supervised approach while requiring 400-fold fewer labeled examples. SegCLR also enables inference of cell types from fragments as small as 10 µm, which enhances the utility of volumes in which many neurites are truncated at boundaries. Finally, SegCLR enables exploration of layer 5 pyramidal cell subtypes and automated large-scale analysis of synaptic partners in mouse visual cortex.

Intestinal bile acids provide a surmountable barrier against C. difficile TcdB-induced disease pathogenesis.

Intestinal bile acids play an essential role in the Clostridioides difficile lifecycle having been shown in vitro to modulate various aspects of pathogenesis, including spore germination, vegetative growth, and more recently the action of the primary virulence determinant, TcdB. Here, we investigated whether physiological levels of the total pool of intestinal bile acids in mice and humans protect against TcdB action. Small molecules extracted from the lumenal contents of the small intestine, cecum, colon, and feces were found to inhibit TcdB in accordance with the differential amounts of total bile acids in each compartment. Extracts from antibiotic-treated and germ-free mice, despite harboring dramatically altered bile acid profiles, unexpectedly also prevented TcdB-induced cell rounding to similar extents. We show that protection, however, is surmountable and can be overcome at higher doses of TcdB-typical to those seen during severe C. difficile infection-suggesting that the protective properties of intestinal bile acids are operant primarily under low to moderate toxin levels. Taken together, these findings demonstrate a role for intestinal bile acids in attenuating virulence, provide insights into asymptomatic carriage of toxigenic C. difficile, and inform strategies to manipulate bile acid levels for therapeutic benefit.

Recent and future declines of a historically widespread pollinator linked to climate, land cover, and pesticides.

The acute decline in global biodiversity includes not only the loss of rare species, but also the rapid collapse of common species across many different taxa. The loss of pollinating insects is of particular concern because of the ecological and economic values these species provide. The western bumble bee (Bombus occidentalis) was once common in western North America, but this species has become increasingly rare through much of its range. To understand potential mechanisms driving these declines, we used Bayesian occupancy models to investigate the effects of climate and land cover from 1998 to 2020, pesticide use from 2008 to 2014, and projected expected occupancy under three future scenarios. Using 14,457 surveys across 2.8 million km2 in the western United States, we found strong negative relationships between increasing temperature and drought on occupancy and identified neonicotinoids as the pesticides of greatest negative influence across our study region. The mean predicted occupancy declined by 57% from 1998 to 2020, ranging from 15 to 83% declines across 16 ecoregions. Even under the most optimistic scenario, we found continued declines in nearly half of the ecoregions by the 2050s and mean declines of 93% under the most severe scenario across all ecoregions. This assessment underscores the tenuous future of B. occidentalis and demonstrates the scale of stressors likely contributing to rapid loss of related pollinator species throughout the globe. Scaled-up, international species-monitoring schemes and improved integration of data from formal surveys and community science will substantively improve the understanding of stressors and bumble bee population trends.

Evolution of a Restriction Factor by Domestication of a Yeast Retrotransposon.

Transposable elements drive genome evolution in all branches of life. Transposable element insertions are often deleterious to their hosts and necessitate evolution of control mechanisms to limit their spread. The long terminal repeat retrotransposon Ty1 prime (Ty1'), a subfamily of the Ty1 family, is present in many Saccharomyces cerevisiae strains, but little is known about what controls its copy number. Here, we provide evidence that a novel gene from an exapted Ty1' sequence, domesticated restriction of Ty1' relic 2 (DRT2), encodes a restriction factor that inhibits Ty1' movement. DRT2 arose through domestication of a Ty1' GAG gene and contains the C-terminal domain of capsid, which in the related Ty1 canonical subfamily functions as a self-encoded restriction factor. Bioinformatic analysis reveals the widespread nature of DRT2, its evolutionary history, and pronounced structural variation at the Ty1' relic 2 locus. Ty1' retromobility analyses demonstrate DRT2 restriction factor functionality, and northern blot and RNA-seq analysis indicate that DRT2 is transcribed in multiple strains. Velocity cosedimentation profiles indicate an association between Drt2 and Ty1' virus-like particles or assembly complexes. Chimeric Ty1' elements containing DRT2 retain retromobility, suggesting an ancestral role of productive Gag C-terminal domain of capsid functionality is present in the sequence. Unlike Ty1 canonical, Ty1' retromobility increases with copy number, suggesting that C-terminal domain of capsid-based restriction is not limited to the Ty1 canonical subfamily self-encoded restriction factor and drove the endogenization of DRT2. The discovery of an exapted Ty1' restriction factor provides insight into the evolution of the Ty1 family, evolutionary hot-spots, and host-transposable element interactions.

Sugar-Sweetened Beverages and Adverse Human Health Outcomes: An Umbrella Review of Meta-Analyses of Observational Studies.

Our aim was to conduct an umbrella review of evidence from meta-analyses of observational studies investigating the link between sugar-sweetened beverage consumption and human health outcomes. Using predefined evidence classification criteria, we evaluated evidence from 47 meta-analyses encompassing 22,055,269 individuals. Overall, 79% of these analyses indicated direct associations between greater sugar-sweetened beverage consumption and higher risks of adverse health outcomes. Convincing evidence (class I) supported direct associations between sugar-sweetened beverage consumption and risks of depression, cardiovascular disease, nephrolithiasis, type 2 diabetes mellitus, and higher uric acid concentrations. Highly suggestive evidence (class II) supported associations with risks of nonalcoholic fatty liver disease and dental caries. Out of the remaining 40 meta-analyses, 29 were graded as suggestive or weak in the strength of evidence (classes III and IV), and 11 showed no evidence (class V). These findings inform and provide support for population-based and public health strategies aimed at reducing sugary drink consumption for improved health.

Proton transfer activity of the reconstituted Mycobacterium tuberculosis MmpL3 is modulated by substrate mimics and inhibitors.

Transporters belonging to the Resistance-Nodulation-cell Division (RND) superfamily of proteins such as Mycobacterium tuberculosis MmpL3 and its analogs are the focus of intense investigations due to their importance in the physiology of Corynebacterium-Mycobacterium-Nocardia species and antimycobacterial drug discovery. These transporters deliver trehalose monomycolates, the precursors of major lipids of the outer membrane, to the periplasm by a proton motive force-dependent mechanism. In this study, we successfully purified, from native membranes, the full-length and the C-terminal truncated M. tuberculosis MmpL3 and Corynebacterium glutamicum CmpL1 proteins and reconstituted them into proteoliposomes. We also generated a series of substrate mimics and inhibitors specific to these transporters, analyzed their activities in the reconstituted proteoliposomes, and carried out molecular dynamics simulations of the model MmpL3 transporter at different pH. We found that all reconstituted proteins facilitate proton translocation across a phospholipid bilayer, but MmpL3 and CmpL1 differ dramatically in their responses to pH and interactions with substrate mimics and indole-2-carboxamide inhibitors. Our results further suggest that some inhibitors abolish the transport activity of MmpL3 and CmpL1 by inhibition of proton translocation.

Ten facts about land systems for sustainability.

Land use is central to addressing sustainability issues, including biodiversity conservation, climate change, food security, poverty alleviation, and sustainable energy. In this paper, we synthesize knowledge accumulated in land system science, the integrated study of terrestrial social-ecological systems, into 10 hard truths that have strong, general, empirical support. These facts help to explain the challenges of achieving sustainability in land use and thus also point toward solutions. The 10 facts are as follows: 1) Meanings and values of land are socially constructed and contested; 2) land systems exhibit complex behaviors with abrupt, hard-to-predict changes; 3) irreversible changes and path dependence are common features of land systems; 4) some land uses have a small footprint but very large impacts; 5) drivers and impacts of land-use change are globally interconnected and spill over to distant locations; 6) humanity lives on a used planet where all land provides benefits to societies; 7) land-use change usually entails trade-offs between different benefits-"win-wins" are thus rare; 8) land tenure and land-use claims are often unclear, overlapping, and contested; 9) the benefits and burdens from land are unequally distributed; and 10) land users have multiple, sometimes conflicting, ideas of what social and environmental justice entails. The facts have implications for governance, but do not provide fixed answers. Instead they constitute a set of core principles which can guide scientists, policy makers, and practitioners toward meeting sustainability challenges in land use.

Offline Two-Dimensional Liquid Chromatography-Mass Spectrometry for Deep Annotation of the Fecal Metabolome Following Fecal Microbiota Transplantation.

Biological interpretation of untargeted LC-MS-based metabolomics data depends on accurate compound identification, but current techniques fall short of identifying most features that can be detected. The human fecal metabolome is complex, variable, incompletely annotated, and serves as an ideal matrix to evaluate novel compound identification methods. We devised an experimental strategy for compound annotation using multidimensional chromatography and semiautomated feature alignment and applied these methods to study the fecal metabolome in the context of fecal microbiota transplantation (FMT) for recurrent C. difficile infection. Pooled fecal samples were fractionated using semipreparative liquid chromatography and analyzed by an orthogonal LC-MS/MS method. The resulting spectra were searched against commercial, public, and local spectral libraries, and annotations were vetted using retention time alignment and prediction. Multidimensional chromatography yielded more than a 2-fold improvement in identified compounds compared to conventional LC-MS/MS and successfully identified several rare and previously unreported compounds, including novel fatty-acid conjugated bile acid species. Using an automated software-based feature alignment strategy, most metabolites identified by the new approach could be matched to features that were detected but not identified in single-dimensional LC-MS/MS data. Overall, our approach represents a powerful strategy to enhance compound identification and biological insight from untargeted metabolomics data.

Ultra-processed food consumption and risk of diabetes: results from a population-based prospective cohort.

AIMS/HYPOTHESIS: Understanding the impact of the overall construct of ultra-processed foods on diabetes risk can inform dietary approaches to diabetes prevention. In this study, we aimed to evaluate the association between ultra-processed food consumption and risk of diabetes in a community-based cohort of middle-aged adults in the USA. We hypothesised that a higher intake of ultra-processed foods is associated with a higher risk of incident diabetes. METHODS: The study included 13,172 participants without diabetes at baseline (1987-1989) in the Atherosclerosis Risk in Communities (ARIC) study. Dietary intake was assessed with a 66-item semiquantitative food frequency questionnaire, and foods were categorised by processing level using the Nova classification system. Ultra-processed food was analysed categorically (quartiles of energy-adjusted intake) and continuously (per one additional serving/day). We used Cox regression to evaluate the association of ultra-processed food intake with risk of diabetes with adjustment for sociodemographic characteristics, total energy intake, health behaviours and clinical factors. RESULTS: Over a median follow-up of 21 years, there were 4539 cases of incident diabetes. Participants in the highest quartile of ultra-processed food intake (8.4 servings/day on average) had a significantly higher risk of diabetes (HR 1.13; 95% CI 1.03, 1.23) compared with participants in the lowest quartile of intake after adjustment for sociodemographic, lifestyle and clinical factors. Each additional serving of ultra-processed food consumed daily was associated with a 2% higher risk of diabetes (HR 1.02; 95% CI 1.00, 1.04). Highest quartile consumption of certain ultra-processed food groups, including sugar- and artificially sweetened beverages, ultra-processed meats and sugary snacks, was associated with a 29%, 21% and 16% higher risk of diabetes, respectively, compared with the lowest quartile. CONCLUSIONS/INTERPRETATION: We found that a higher intake of ultra-processed food was associated with higher risk of incident diabetes, particularly sugar- and artificially sweetened beverages, ultra-processed meats and sugary snacks. Our findings suggest interventions reducing ultra-processed food consumption and specific food groups may be an effective strategy for diabetes prevention.

Chemical Annealing Restructures RNA for Nanopore Detection.

RNA is a key biochemical marker, yet its chemical instability and complex secondary structure hamper its integration into DNA nanotechnology-based sensing platforms. Relying on the denaturation of the native RNA structure using urea, we show that restructured DNA/RNA hybrids can readily be prepared at room temperature. Using solid-state nanopore sensing, we demonstrate that the structures of our DNA/RNA hybrids conform to the design at the single-molecule level. Employing this chemical annealing procedure, we mitigate RNA self-cleavage, enabling the direct detection of restructured RNA molecules for biosensing applications.

Characterization of mismatch-repair/microsatellite instability-discordant endometrial cancers.

BACKGROUND: Mismatch-repair (MMR)/microsatellite instability (MSI) status has therapeutic implications in endometrial cancer (EC). The authors evaluated the concordance of testing and factors contributing to MMR expression heterogeneity. METHODS: Six hundred sixty-six ECs were characterized using immunohistochemistry (IHC), MSI testing, and mut-L homolog 1 (MLH1) methylation. Select samples underwent whole-transcriptome analysis and next-generation sequencing. MMR expression of metastatic/recurrent sites was evaluated. RESULTS: MSI testing identified 27.3% of cases as MSI-high (n = 182), MMR IHC identified 25.1% cases as MMR-deficient (n = 167), and 3.8% of cases (n = 25) demonstrated discordant results. A review of IHC staining explained discordant results in 18 cases, revealing subclonal loss of MLH1/Pms 1 homolog 2 (PMS2) (n = 10) and heterogeneous MMR IHC (mut-S homolog 6 [MSH6], n = 7; MLH1/PMS2, n = 1). MSH6-associated Lynch syndrome was diagnosed in three of six cases with heterogeneous expression. Subclonal or heterogeneous cases had a 38.9% recurrence rate (compared with 16.7% in complete MMR-deficient cases and 9% in MMR-proficient cases) and had abnormal MMR IHC results in all metastatic recurrent sites (n = 7). Tumors with subclonal MLH1/PMS2 demonstrated 74 differentially expressed genes (determined using digital spatial transcriptomics) when stratified by MLH1 expression, including many associated with epithelial-mesenchymal transition. CONCLUSIONS: Subclonal/heterogeneous MMR IHC cases showed epigenetic loss in 66.7%, germline mutations in 16.7%, and somatic mutations in 16.7%. MMR IHC reported as intact/deficient missed 21% of cases of Lynch syndrome. EC with subclonal/heterogeneous MMR expression demonstrated a high recurrence rate, and metastatic/recurrent sites were MMR-deficient. Transcriptional analysis indicated an increased risk for migration/metastasis, suggesting that clonal MMR deficiency may be a driver for tumor aggressiveness. Reporting MMR IHC only as intact/deficient, without reporting subclonal and heterogeneous staining, misses opportunities for biomarker-directed therapy. PLAIN LANGUAGE SUMMARY: Endometrial cancer is the most common gynecologic cancer, and 20%-40% of tumors have a defect in DNA proofreading known as mismatch-repair (MMR) deficiency. These results can be used to guide therapy. Tests for this defect can yield differing results, revealing heterogeneous (mixed) proofreading capabilities. Tumors with discordant testing results and mixed MMR findings can have germline or somatic defects in MMR genes. Cells with deficient DNA proofreading in tumors with mixed MMR findings have DNA expression profiles linked to more aggressive characteristics and cancer spread. These MMR-deficient cells may drive tumor behavior and the risk of spreading cancer.

Plant-based diets for kidney disease prevention and treatment.

PURPOSE OF REVIEW: Plant-based diets are associated with a lower risk of hypertension, diabetes, cardiovascular disease, and mortality. Using the most recent evidence, we critically appraised the role of plant-based diets in primary and secondary prevention of chronic kidney disease (CKD) with a focus on key nutritional factors (dietary acid load, phosphorus, potassium, sodium, and fiber). RECENT FINDINGS: In healthy individuals, observational studies found that greater intake of plant protein and higher adherence to plant-based diets (overall, healthful, and provegetarian) was associated with a lower risk of CKD. In those with CKD, plant-based diets were associated with a lower risk of mortality, improved kidney function, and favorable metabolic profiles (fibroblast growth factor-23, uremic toxins, insulin sensitivity, inflammatory biomarkers). Only few studies reported nutrient content of plant-based diets. These studies found that plant-based diets had lower dietary acid load, lower or no significant difference in phosphorus and sodium, and higher potassium and fiber. One study reported that vegetarian diets were associated with severe vitamin D deficiency compared to nonvegetarian diets. SUMMARY: Plant-based diets provide several benefits for prevention and management of CKD, with little risk for individuals with CKD. Incorporation of vitamin D rich foods in plant-based diets may be helpful.

Adherence to Plant-Based Diets and Risk of CKD Progression and All-Cause Mortality: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study.

RATIONALE & OBJECTIVE: Studies have shown that generally healthy individuals who consume diets rich in plant foods have a lower risk of incident chronic kidney disease (CKD) and cardiovascular disease. This study investigated the prospective associations of plant-based diets with the risk of CKD progression and all-cause mortality in individuals with CKD. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 2,539 participants with CKD recruited between 2003-2008 into the Chronic Renal Insufficiency Cohort (CRIC) Study. EXPOSURE: Responses on the Diet History Questionnaire were used to calculate scores for the overall plant-based diet index, healthy plant-based diet index, and unhealthy plant-based diet index. OUTCOME: (1) CKD progression defined as≥50% estimated glomerular filtration rate decline from baseline or kidney replacement therapy (dialysis, transplant) and (2) all-cause mortality. ANALYTICAL APPROACH: Cox proportional hazards models to compute hazard ratios and 95% confidence intervals adjusting for lifestyle, socioeconomic, and clinical covariates. RESULTS: There were 977 CKD progression events and 836 deaths during a median follow-up period of 7 and 12 years, respectively. Participants with the highest versus lowest adherence to overall plant-based diets and healthy plant-based diets had 26% (HR, 0.74 [95% CI, 0.62-0.88], P trend<0.001) and 21% (HR, 0.79 [95% CI, 0.66-0.95], P trend=0.03) lower risks of all-cause mortality, respectively. Each 10-point higher score of unhealthy plant-based diets was modestly associated with a higher risk of CKD progression (HR, 1.14 [95% CI, 1.03-1.25) and all-cause mortality (HR, 1.11 [95% CI, 1.00-1.23). LIMITATIONS: Self-reported diet may be subject to measurement error. CONCLUSIONS: Adherence to an overall plant-based diet and a healthy plant-based diet is associated with a reduced risk of all-cause mortality among individuals with CKD. An unhealthy plant-based was associated with an elevated risk of CKD progression and all-cause mortality. PLAIN-LANGUAGE SUMMARY: Plant-based diets are healthful dietary patterns that have been linked to a lower risk of chronic diseases. However, the impact of plant-based diets on clinical outcomes in patients with chronic kidney disease (CKD) is not well established. In 2,539 individuals with CKD, we examined the associations of adherence to 3 different types of plant-based diets with the risks of CKD progression and all-cause mortality. We found that following an overall plant-based diet and a healthy plant-based diet was associated with a lower risk of all-cause mortality. By contrast, following an unhealthy plant-based diet was associated with a higher risk of CKD progression and all-cause mortality. These results suggest that the quality of plant-based diets may be important for CKD management.

Association Between Racial and Socioeconomic Disparities and Hospital Performance in Treatment and Outcomes for Patients with Colon Cancer.

BACKGROUND: Disparities in colon cancer care and outcomes by race/ethnicity, socioeconomic status (SES), and insurance are well recognized; however, the extent to which inequalities are driven by patient factors versus variation in hospital performance remains unclear. We sought to compare disparities in care delivery and outcomes at low- and high-performing hospitals. METHODS: We identified patients with stage I-III colon adenocarcinoma from the 2012-2017 National Cancer Database. Adequate lymphadenectomy and timely adjuvant chemotherapy administration defined hospital performance. Multilevel regression models evaluated disparities by race/ethnicity, SES, and insurance at the lowest- and highest-performance quartile hospitals. RESULTS: Of 92,573 patients from 704 hospitals, 45,982 (49.7%) were treated at 404 low-performing hospitals and 46,591 (50.3%) were treated at 300 high-performing hospitals. Low-performing hospitals treated more non-Hispanic (NH) Black, Hispanic, low SES, and Medicaid patients (all p < 0.01). Among low-performing hospitals, patients with low versus high SES (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.82-0.92), and Medicare (OR 0.90, 95% CI 0.85-0.96) and Medicaid (OR 0.88, 95% CI 0.80-0.96) versus private insurance, had decreased odds of receiving high-quality care. At high-performing hospitals, NH Black versus NH White patients (OR 0.83, 95% CI 0.72-0.95) had decreased odds of receiving high-quality care. Low SES, Medicare, Medicaid, and uninsured patients had worse overall survival at low- and high-performing hospitals (all p < 0.01). CONCLUSION: Disparities in receipt of high-quality colon cancer care occurred by SES and insurance at low-performing hospitals, and by race at high-performing hospitals. However, survival disparities by SES and insurance exist irrespective of hospital performance. Future steps include improving low-performing hospitals and identifying mechanisms affecting survival disparities.

Access, Outcomes, and Costs Associated with Surgery for Malignancy Among People Experiencing Homelessness.

BACKGROUND: Little is known about surgery for malignancy among people experiencing homelessness (PEH). Poor healthcare access may lead to delayed diagnosis and need for unplanned surgery. This study aimed to (1) characterize access to care among PEH, (2) evaluate postoperative outcomes, and (3) assess costs associated with surgery for malignancy among PEH. METHODS: This was a retrospective cohort study of patients in the Healthcare Cost and Utilization Project (HCUP) who underwent surgery in Florida, New York, or Massachusetts for gastrointestinal or lung cancer from 2016 to 2017. PEH were identified using HCUP's "Homeless" variable and ICD-10 code Z59. Multivariable regression models controlling patient and hospital variables evaluated associations between homelessness and postoperative morbidity, length of stay (LOS), 30-day readmission, and hospitalization costs. RESULTS: Of 67,034 patients at 566 hospitals, 98 (0.2%) were PEH. Most PEH (44.9%) underwent surgery for colorectal cancer. PEH more frequently underwent unplanned surgery than housed patients (65.3% vs 23.7%, odds ratio (OR) 5.17, 95% confidence interval (CI) 3.00-8.92) and less often were treated at cancer centers (66.0% vs 76.2%, p=0.02). Morbidity rates were similar between groups (20.4% vs 14.5%, p=0.10). However, PEH demonstrated higher odds of facility discharge (OR 5.89, 95% CI 3.50-9.78) and readmission (OR 1.81, 95% CI 1.07-3.05) as well as 67.7% longer adjusted LOS (95% CI 42.0-98.2%). Adjusted costs were 32.7% higher (95% CI 14.5-53.9%) among PEH. CONCLUSIONS: PEH demonstrated increased odds of unplanned surgery, longer LOS, and increased costs. These results underscore a need for improved access to oncologic care for PEH.

Trends in Plant-Based Diets among United States Adults, 1999-March 2020.

BACKGROUND: Interest in plant-based eating has increased alongside increased variety and availability of highly processed plant-based meat and dairy alternatives. The impact of the shifting commercial landscape and public interest in plant-based eating on dietary intake is unknown. OBJECTIVES: To examine trends in the consumption and composition of plant-based diets in the United States adults. METHODS: Serial cross-sectional data from the National Health and Nutrition Examination Survey were used to assess trends in the proportion of United States adults aged ≥20 y consuming a plant-based diet (defined as ≥50% total protein from plants on a 24-h dietary recall) from 1999-2000 to 2017-March 2020 (n = 51,698). Trends in processing level (percentage energy intake from ultraprocessed foods) and diet quality [Healthy Eating Index (HEI)-2020 scores] were assessed in the subset of adults consuming plant-based diets (n = 8327). RESULTS: The proportion of United States adults consuming plant-based diets increased from 14.4% (95% CI: 12.9%, 16.0%) to 17.2% (95% confidence interval [CI]: 15.5%, 19.1%; P = 0.005 for trend). In all survey cycles, ultraprocessed foods accounted for the majority of energy intake, and ultraprocessed food intake in plant-based diets did not significantly change over time [50.7% kcal (95% CI: 47.3%, 54.1%) in 1999-2000 compared with 52.7% kcal (95% CI: 49.7%, 55.6%) in 2017-March 2020; P for trend = 0.34]. The quality of plant-based diets, measured by HEI-2020 scores, improved from 52.1 (95% CI: 49.7, 54.6) to 55.8 (95% CI: 54.1, 57.5; P for trend <0.001). CONCLUSIONS: Between 1999 and March 2020, the proportion of United States adults consuming a plant-based diet increased. Among people consuming plant-based diets, ultraprocessed foods contributed most to energy intake and there was no sustained change in intake over time. The mean diet quality was low but improved modestly.