Mycobacterium abscessus HelR interacts with RNA polymerase to confer intrinsic rifamycin resistance.

Rifampicin (RIF), the frontline drug against M. tuberculosis, is completely ineffective against M. abscessus, partially due to the presence of an ADP-ribosyltransferase (Arr) that inactivates RIF. Using RNA-seq, we show that exposure of M. abscessus to sublethal doses of RIF and Rifabutin (RBT), a close analog of RIF, results in an ∼25-fold upregulation of Mab_helR in laboratory and clinical isolates. An isogenic deletion in Mab_helR results in RIF/RBT hypersensitivity, and overexpression of Mab_helR confers RIF tolerance in M. tuberculosis. We demonstrate an increased HelR-RNAP association in RIF-exposed bacteria and a MabHelR-mediated dissociation of RNAP from stalled initiation complexes in vitro. Finally, we show that the tip of the PCh-loop of Mab_helR, present in proximity to RIF, is critical for conferring RIF resistance but dispensable for dissociation of stalled RNAP complexes, suggesting that HelR-mediated RIF resistance requires a step in addition to displacement of RIF-stalled RNAP.

Factor XI Inhibition for the Prevention of Catheter-Associated Thrombosis in Patients With Cancer Undergoing Central Line Placement: A Phase 2 Clinical Trial.

BACKGROUND: Despite the ubiquitous utilization of central venous catheters in clinical practice, their use commonly provokes thromboembolism. No prophylactic strategy has shown sufficient efficacy to justify routine use. Coagulation factors FXI (factor XI) and FXII (factor XII) represent novel targets for device-associated thrombosis, which may mitigate bleeding risk. Our objective was to evaluate the safety and efficacy of an anti-FXI mAb (monoclonal antibody), gruticibart (AB023), in a prospective, single-arm study of patients with cancer receiving central line placement. METHODS: We enrolled ambulatory cancer patients undergoing central line placement to receive a single dose of gruticibart (2 mg/kg) administered through the venous catheter within 24 hours of placement and a follow-up surveillance ultrasound at day 14 for evaluation of catheter thrombosis. A parallel, noninterventional study was used as a comparator. RESULTS: In total, 22 subjects (n=11 per study) were enrolled. The overall incidence of catheter-associated thrombosis was 12.5% in the interventional study and 40.0% in the control study. The anti-FXI mAb, gruticibart, significantly prolonged the activated partial thromboplastin time in all subjects on day 14 compared with baseline (P<0.001). Gruticibart was well tolerated and without infusion reactions, drug-related adverse events, or clinically relevant bleeding. Platelet flow cytometry demonstrated no difference in platelet activation following administration of gruticibart. T (thrombin)-AT (antithrombin) and activated FXI-AT complexes increased following central line placement in the control study, which was not demonstrated in our intervention study. CRP (C-reactive protein) did not significantly increase on day 14 in those who received gruticibart, but it did significantly increase in the noninterventional study. CONCLUSIONS: FXI inhibition with gruticibart was well tolerated without any significant adverse or bleeding-related events and resulted in a lower incidence of catheter-associated thrombosis on surveillance ultrasound compared with the published literature and our internal control study. These findings suggest that targeting FXI could represent a safe intervention to prevent catheter thrombosis. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04465760.

Cytoprotective E-WE thrombin reduces disease severity in a murine model of relapsing-remitting multiple sclerosis.

The blood-brain barrier is composed of microvascular endothelial cells, immune cells, and astrocytes that work in concert with the coagulation cascade to control inflammation and immune cell infiltration into the central nervous system. Endothelial cell dysfunction leading to increased permeability and compromised barrier function are hallmarks of neuroinflammatory and autoimmune disorders, including multiple sclerosis (MS). Therapeutic strategies that improve or protect endothelial barrier function may be beneficial in the treatment or prevention of neuroinflammatory diseases. We therefore tested the hypothesis that biasing thrombin toward anticoagulant and cytoprotective activities would provide equivalent or even additive benefit compared with standard-of-care therapeutic strategies, including corticosteroids. In a mouse model of relapsing-remitting MS, treatment with the thrombin mutant, E-WE thrombin, an engineered thrombin mutant with cytoprotective activities that is biased toward anticoagulant and cytoprotective activity, reduced neuroinflammation and extracellular fibrin formation in SJL mice inoculated with proteolipid protein (PLP) peptide. When administered at the onset of detectable disease, E-WE thrombin significantly improved the disease severity of the initial attack as well as the relapse and delayed the onset of relapse to a similar extent as observed with methylprednisolone. Both methylprednisolone and E-WE thrombin reduced demyelination and immune cell recruitment. These results provide rationale for considering engineered forms of thrombin biased toward anticoagulant and cytoprotective activity as a therapeutic strategy and perhaps an effective alternative to high-dose methylprednisolone for the management of acute relapsing MS attacks.NEW & NOTEWORTHY There are limited treatment options for mitigating acute relapsing attacks for patients with multiple sclerosis. We tested the hypothesis that harnessing the cytoprotective activity of the blood coagulation enzyme, thrombin, would provide benefit and protection against relapsing disease in a mouse model of MS. Our results provide rationale for considering engineered forms of thrombin biased toward cytoprotective activity as a therapeutic strategy and perhaps an alternative to steroids for the management of relapsing MS attacks.

Exploring the Relationship Between Efpeglenatide Dose and Cardiovascular Outcomes in Type 2 Diabetes: Insights From the AMPLITUDE-O Trial.

BACKGROUND: In the AMPLITUDE-O (Effect of Efpeglenatide on Cardiovascular Outcomes) cardiovascular outcomes trial, adding either 4 mg or 6 mg weekly of the glucagon-like peptide-1 receptor agonist efpeglenatide to usual care reduced major adverse cardiovascular events (MACE) in people with type 2 diabetes at high cardiovascular risk. Whether these benefits are dose related remains uncertain. METHODS: Participants were randomly assigned in a 1:1:1 ratio to placebo, 4 mg or 6 mg of efpeglenatide. The effect of 6 mg versus placebo and of 4 mg versus placebo on MACE (a nonfatal myocardial infarction, nonfatal stroke, or death from cardiovascular or unknown causes) and on all the secondary composite cardiovascular and kidney outcomes was assessed. A dose-response relationship was assessed using the log-rank test and χ2 statistic for trend. RESULTS: During a median follow-up of 1.8 years, MACE occurred in 125 (9.2%) participants assigned to placebo, 84 (6.2%) participants assigned to 6 mg of efpeglenatide (hazard ratio [HR], 0.65 [95% CI, 0.5-0.86]; P=0.0027), and 105 (7.7%) assigned to 4 mg of efpeglenatide (HR, 0.82 [95% CI, 0.63-1.06]; P=0.14). Participants receiving high-dose efpeglenatide also experienced fewer secondary outcomes, including the composite of MACE, coronary revascularization, or hospitalization for unstable angina (HR, 0.73 for 6 mg, P=0.011; HR, 0.85 for 4 mg, P=0.17), a kidney composite outcome comprising sustained new macroalbuminuria, a ≥40% decline in estimated glomerular filtration rate or renal failure (HR, 0.63 for 6 mg, P<0.0001; HR, 0.73 for 4 mg, P=0.0009), MACE or any death (HR, 0.67 for 6 mg, P=0.0021; HR, 0.81 for 4 mg, P=0.08), a kidney function outcome comprising a sustained ≥40% decline in estimated glomerular filtration rate, renal failure, or death (HR, 0.61 for 6 mg, P=0.0072; HR, 0.97 for 4 mg, P=0.83), and the composite of MACE, any death, heart failure hospitalization, or the kidney function outcome (HR, 0.63 for 6 mg, P=0.0002; HR, 0.81 for 4 mg, P=0.067). A clear dose-response was noted for all primary and secondary outcomes (all P for trend ≤0.018). CONCLUSIONS: The graded salutary relationship between efpeglenatide dose and cardiovascular outcomes suggests that titrating efpeglenatide and potentially other glucagon-like peptide-1 receptor agonists to high doses may maximize their cardiovascular and renal benefits. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03496298.

Four-year overall survival update from the phase III HIMALAYA study of tremelimumab plus durvalumab in unresectable hepatocellular carcinoma.

BACKGROUND: In the phase III HIMALAYA study (NCT03298451) in unresectable hepatocellular carcinoma (uHCC), STRIDE (Single Tremelimumab Regular Interval Durvalumab) significantly improved overall survival (OS) versus sorafenib; durvalumab monotherapy was noninferior to sorafenib for OS. Results reported herein are from a 4-year updated OS analysis of HIMALAYA. PATIENTS AND METHODS: Participants with uHCC and no previous systemic treatment were randomized to STRIDE (n = 393), durvalumab (n = 389), or sorafenib (n = 389). The updated data cut-off was 23 January 2023. OS and serious adverse events (AEs) were assessed. Additionally, baseline characteristics and subsequent therapies were analyzed in long-term survivors (≥36 months beyond randomization). RESULTS: For STRIDE, durvalumab, and sorafenib, median [95% confidence interval (CI)] follow-up was 49.12 months (46.95-50.17 months), 48.46 months (46.82-49.81 months), and 47.31 months (45.08-49.15 months), respectively. OS hazard ratio (95% CI) for STRIDE versus sorafenib was 0.78 (0.67-0.92). The 36-month OS rate for STRIDE was 30.7% versus 19.8% for sorafenib. The 48-month OS rate remained higher for STRIDE at 25.2%, versus 15.1% for sorafenib. The long-term OS benefit of STRIDE was observed across clinically relevant subgroups and was further improved in participants who achieved disease control. Long-term survivors with STRIDE (n = 103) included participants across clinically relevant subgroups, and 57.3% (59/103) had no reported subsequent anticancer therapy. No new serious treatment-related AEs occurred with STRIDE from the primary analysis (17.5%; 68/388). Durvalumab maintained OS noninferiority to sorafenib and no late-onset safety signals were identified. CONCLUSIONS: These data represent the longest follow-up to date in phase III studies in uHCC. The unprecedented 3- and 4-year OS rates reinforce the sustained long-term OS benefit of STRIDE versus sorafenib. STRIDE maintained a tolerable yet differentiated safety profile from other current uHCC therapies. Results continue to support the long-term benefits of STRIDE in a diverse population, reflective of uHCC globally.

ICAT: a novel algorithm to robustly identify cell states following perturbations in single-cell transcriptomes.

MOTIVATION: The detection of distinct cellular identities is central to the analysis of single-cell RNA sequencing (scRNA-seq) experiments. However, in perturbation experiments, current methods typically fail to correctly match cell states between conditions or erroneously remove population substructure. Here, we present the novel, unsupervised algorithm Identify Cell states Across Treatments (ICAT) that employs self-supervised feature weighting and control-guided clustering to accurately resolve cell states across heterogeneous conditions. RESULTS: Using simulated and real datasets, we show ICAT is superior in identifying and resolving cell states compared with current integration workflows. While requiring no a priori knowledge of extant cell states or discriminatory marker genes, ICAT is robust to low signal strength, high perturbation severity, and disparate cell type proportions. We empirically validate ICAT in a developmental model and find that only ICAT identifies a perturbation-unique cellular response. Taken together, our results demonstrate that ICAT offers a significant improvement in defining cellular responses to perturbation in scRNA-seq data. AVAILABILITY AND IMPLEMENTATION: https://github.com/BradhamLab/icat.

Cardiovascular and renal outcomes with varying degrees of kidney disease in high-risk people with type 2 diabetes: An epidemiological analysis of data from the AMPLITUDE-O trial.

AIMS: To estimate the incidence of a major adverse cardiovascular event (MACE) and a composite kidney outcome across estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR) levels, and to determine whether efpeglenatide's effect varies with these indices. MATERIALS AND METHODS: AMPLITUDE-O trial data were used to estimate the relationship of eGFR, UACR, and Kidney Disease Improving Global Outcomes (KDIGO) category to the hazard of MACE and the kidney composite. Interactions on these outcomes between eGFR and the UACR, and between each of these variables and efpeglenatide were also assessed. RESULTS: Baseline eGFR and UACR were available for 3983 participants (mean age 64.5 years). During a median follow-up of 1.8 years, the hazards of MACE and the kidney composite for the lowest versus highest eGFR third were 1.6 (95% confidence interval [CI] 1.2, 2.2) and 2.3 (95% CI 1.9, 2.8), respectively. The hazards for the highest versus the lowest UACR third were 2.3 (95% CI 1.8, 3.1) and 18.0 (95% CI 12.7, 25.5), respectively, and for the high- versus low-risk KDIGO categories the hazards were 2.4 (95% CI 1.8, 3.1) and 16.0 (95% CI 11.6, 22.0), respectively. eGFR and UACR were independent determinants of both outcomes, but negatively interacted with each other for the kidney outcome. Efpeglenatide's effect on both outcomes did not vary with any kidney disease measure (all interaction p values ≥0.26). CONCLUSIONS: In high-risk people with diabetes, eGFR, UACR, and KDIGO category have different relationships to incident cardiovascular and kidney outcomes. The beneficial effect of efpeglenatide on these outcomes is independent of kidney-related risk category.

Impact of a Pediatric Emergency Medicine Pharmacist, Institutional Guideline, and Electronic Order Set on Empiric Antimicrobial Use for Febrile Neutropenia.

OBJECTIVES: This study evaluated the difference in appropriateness of antimicrobial selection in pediatric patients with febrile neutropenia (FN) after implementation of an institutional guideline, a dedicated pediatric emergency medicine (EM) pharmacist, and an electronic order set. METHODS: This was a retrospective cohort study that included febrile patients aged younger than 18 years who were at risk of neutropenia, as defined by our institutional algorithm. Charts were evaluated for inclusion by searching for patients who presented to the emergency department (ED) between February 2018 and January 2022 who had International Classification of Diseases, Tenth Revision (ICD-10) codes for patients at risk of FN. Three independent groups were compared before, during, and after interventions. A historical control group (group 1), postdedicated EM pharmacist and institutional guideline cohort (group 2), and postdedicated EM pharmacist, institutional guideline, and electronic order set cohort (group 3) were compared. Secondary outcomes included time from registration in the ED to administration of the first dose of empiric antimicrobials, days to defervescence, pediatric intensive care unit length of stay, and hospital length of stay. RESULTS: Seventy-eight charts were reviewed for inclusion. Among those included (n = 38), there was an increase in appropriate use of antimicrobials from 71% to 92% to 100% ( P = 0.1534) between group 1, group 2, and group 3, respectively. In addition, the interventions in this study lead to an overall decrease in the median time from registration to first dose of antibiotics from 142 minutes to 72 minutes ( P = 0.1370). CONCLUSIONS: This study demonstrated the positive impact a pediatric EM pharmacist along with an institutional guideline and an electronic order set have on appropriate antimicrobial selection in pediatric FN patients. Institutions should consider multipronged approaches to improve the selection and time to administration of appropriate empiric antimicrobials in the ED.

Impact of Attentional Focus on Dance Performance: A Critically Appraised Topic.

CLINICAL SCENARIO: Dancing is a demanding esthetic activity with dancers having an 85% annual injury incident rate when performing complex dance motor skills. Teachers and clinicians use a combination of external and internal attentional cues when teaching dancers motor skills and when working on rehabilitation programs with injured dancers, respectively. External attentional focus (ie, focusing on movement outcome) reportedly results in superior performance than internal attentional focus (ie, focus on body movements). Interestingly, dancers reportedly often adopt an internal focus when dancing. Still, limited literature exists examining the effects of attentional focus on dancers' performance. CLINICAL QUESTION: How does attentional focus (external or internal) impact performance in dancers? SUMMARY OF KEY FINDINGS: Four original quasi-experimental studies met inclusion criteria. In the current examination, we found mixed results about the impact of attentional focus in dancers. Specifically, using an external attentional focus resulted in better performance in 2 studies, but these findings were limited to lesser experienced dancers. Experienced dancers did not have any physical performance differences when using external or internal focus. Internal focus also did not negatively affect dancers' performance in 2 studies. Some authors noted positive motivational effects (eg, increased perceived competence) when dancers used external focus. CLINICAL BOTTOM LINE: Low-quality evidence exists supporting the notion that in less experienced dance students, external focus improves performance. In experienced dancers, the type of attentional focus did not impact performance. External focus provides positive mental effects. Thus, clinicians working with dancers can integrate individualized feedback according to dancer level, with a preference toward external focus due to positive mental effects, to design optimal training and rehabilitation programs. STRENGTH OF RECOMMENDATION: Grade B evidence exists supporting the notion that an external attentional focus improves performance in less experienced dance students and also has positive mental effects. Internal attentional focus does not impede experienced dancers' performance.

Efpeglenatide and Clinical Outcomes With and Without Concomitant Sodium-Glucose Cotransporter-2 Inhibition Use in Type 2 Diabetes: Exploratory Analysis of the AMPLITUDE-O Trial.

BACKGROUND: Both sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists reduce cardiovascular events among patients with type 2 diabetes. However, no cardiovascular outcome trial has evaluated the long-term effects of their combined use. The AMPLITUDE-O trial (Effect of Efpeglenatide on Cardiovascular Outcomes) reported that once-weekly injections of the glucagon-like peptide-1 receptor agonists efpeglenatide (versus placebo) reduced major adverse cardiovascular events (MACEs); MACEs, coronary revascularization, or unstable angina hospitalization (expanded MACEs); a renal composite outcome; and MACEs or death in people with type 2 diabetes and cardiovascular or renal disease. The trial uniquely stratified randomization by baseline or anticipated use of SGLT2 inhibitors and included the highest prevalence at baseline (N=618, 15.2%) of SGLT2 inhibitor use among glucagon-like peptide-1 receptor agonist cardiovascular outcome trials to date. Its results were analyzed to estimate the combined effect of SGLT2 inhibitors and efpeglenatide on clinical outcomes. METHODS: Cardiovascular and renal outcomes were analyzed with Cox proportional hazards models adjusted for region, SGLT2 inhibitor randomization strata, and the SGLT2 inhibitor-by-treatment interaction. Continuous variables were analyzed with a mixed-effects models for repeated measures that also included an interaction term. RESULTS: The effect (hazard ratio [95% CI]) of efpeglenatide versus placebo in the absence and presence of baseline SGLT2 inhibitors on MACEs (0.74 [0.58-0.94] and 0.70 [0.37-1.30], respectively), expanded MACEs (0.77 [0.62-0.96] and 0.87 [0.51-1.48]), renal composite (0.70 [0.59-0.83] and 0.52 [0.33-0.83]), and MACEs or death (0.74 [0.59-0.93] and 0.65 [0.36-1.19]) did not differ by baseline SGLT2 inhibitor use (P for all interactions >0.2). The reduction of blood pressure, body weight, low-density lipoprotein cholesterol, and urinary albumin-to-creatinine ratio by efpeglenatide also appeared to be independent of concurrent SGLT2 inhibitor use (all interaction P≥0.08). Last, adverse events did not differ by baseline SGLT2 inhibitor use. CONCLUSIONS: The efficacy and safety of efpeglenatide appear to be independent of concurrent SGLT2 inhibitor use. These data support combined SGLT2 inhibitor and glucagon-like peptide-1 receptor agonist therapy in type 2 diabetes. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03496298.

Total events and net clinical benefit of rivaroxaban and aspirin in patients with chronic coronary or peripheral artery disease: The COMPASS trial.

BACKGROUND: Low dose rivaroxaban with aspirin reduced major cardiovascular events (MACE) compared to aspirin alone in patients with cardiovascular disease although effects on total events are unknown. METHODS: The COMPASS clinical trial randomized 27,395 participants with chronic coronary and/or peripheral artery disease to rivaroxaban 2.5 mg twice daily plus aspirin 100 mg daily, rivaroxaban 5 mg twice daily alone, or aspirin 100 mg daily. We analyzed total (first and recurrent) MACE outcomes of cardiovascular death, stroke, or myocardial infarction, and the primary safety outcome of major bleeding. Exploratory analyses included on-treatment and net clinical benefit. Total MACE and safety events were modeled for each treatment. RESULTS: MACE events were lowest in rivaroxaban with aspirin (379 first MACE, 432 total MACE) compared with rivaroxaban (448 first, 508 total) or aspirin alone (496 first, 574 total). Rivaroxaban and aspirin reduced total MACE events compared with aspirin alone [HR 0.75, 95% CI 0.66-0.85, P < .0001, number needed to treat for 2 years (NNT2y) of 63]. Total major bleeding was higher for rivaroxaban with aspirin compared to aspirin, but severe bleeding was not increased. The net clinical benefit of rivaroxaban plus aspirin was 20% higher compared with aspirin alone [HR 0.80 (95% CI 16.3%-31.6%)]. Rivaroxaban alone had no benefit on MACE outcomes compared with aspirin alone. MACE outcomes were similar for those on and off randomized treatment. CONCLUSIONS: Low dose rivaroxaban with aspirin significantly reduces first and total cardiovascular events compared with aspirin alone with a NNT2y of 63 and a 20% net clinical benefit. TRIAL REGISTRATION: NCT01776424. https://clinicaltrials.gov/ct2/show/NCT01776424.

NCCN Guidelines® Insights: Biliary Tract Cancers, Version 2.2023.

In 2023, the NCCN Guidelines for Hepatobiliary Cancers were divided into 2 separate guidelines: Hepatocellular Carcinoma and Biliary Tract Cancers. The NCCN Guidelines for Biliary Tract Cancers provide recommendations for the evaluation and comprehensive care of patients with gallbladder cancer, intrahepatic cholangiocarcinoma, and extrahepatic cholangiocarcinoma. The multidisciplinary panel of experts meets at least on an annual basis to review requests from internal and external entities as well as to evaluate new data on current and emerging therapies. These Guidelines Insights focus on some of the recent updates to the NCCN Guidelines for Biliary Tract Cancers as well as the newly published section on principles of molecular testing.

Mycobacterial HflX is a ribosome splitting factor that mediates antibiotic resistance.

Antibiotic resistance in bacteria is typically conferred by proteins that function as efflux pumps or enzymes that modify either the drug or the antibiotic target. Here we report an unusual mechanism of resistance to macrolide-lincosamide antibiotics mediated by mycobacterial HflX, a conserved ribosome-associated GTPase. We show that deletion of the hflX gene in the pathogenic Mycobacterium abscessus, as well as the nonpathogenic Mycobacterium smegmatis, results in hypersensitivity to the macrolide-lincosamide class of antibiotics. Importantly, the level of resistance provided by Mab_hflX is equivalent to that conferred by erm41, implying that hflX constitutes a significant resistance determinant in M. abscessus We demonstrate that mycobacterial HflX associates with the 50S ribosomal subunits in vivo and can dissociate purified 70S ribosomes in vitro, independent of GTP hydrolysis. The absence of HflX in a ΔMs_hflX strain also results in a significant accumulation of 70S ribosomes upon erythromycin exposure. Finally, a deletion of either the N-terminal or the C-terminal domain of HflX abrogates ribosome splitting and concomitantly abolishes the ability of mutant proteins to mediate antibiotic tolerance. Together, our results suggest a mechanism of macrolide-lincosamide resistance in which the mycobacterial HflX dissociates antibiotic-stalled ribosomes and rescues the bound mRNA. Given the widespread presence of hflX genes, we anticipate this as a generalized mechanism of macrolide resistance used by several bacteria.

Global Variations in Heart Failure Etiology, Management, and Outcomes.

Importance: Most epidemiological studies of heart failure (HF) have been conducted in high-income countries with limited comparable data from middle- or low-income countries. Objective: To examine differences in HF etiology, treatment, and outcomes between groups of countries at different levels of economic development. Design, Setting, and Participants: Multinational HF registry of 23 341 participants in 40 high-income, upper-middle-income, lower-middle-income, and low-income countries, followed up for a median period of 2.0 years. Main Outcomes and Measures: HF cause, HF medication use, hospitalization, and death. Results: Mean (SD) age of participants was 63.1 (14.9) years, and 9119 (39.1%) were female. The most common cause of HF was ischemic heart disease (38.1%) followed by hypertension (20.2%). The proportion of participants with HF with reduced ejection fraction taking the combination of a ß-blocker, renin-angiotensin system inhibitor, and mineralocorticoid receptor antagonist was highest in upper-middle-income (61.9%) and high-income countries (51.1%), and it was lowest in low-income (45.7%) and lower-middle-income countries (39.5%) (P < .001). The age- and sex- standardized mortality rate per 100 person-years was lowest in high-income countries (7.8 [95% CI, 7.5-8.2]), 9.3 (95% CI, 8.8-9.9) in upper-middle-income countries, 15.7 (95% CI, 15.0-16.4) in lower-middle-income countries, and it was highest in low-income countries (19.1 [95% CI, 17.6-20.7]). Hospitalization rates were more frequent than death rates in high-income countries (ratio = 3.8) and in upper-middle-income countries (ratio = 2.4), similar in lower-middle-income countries (ratio = 1.1), and less frequent in low-income countries (ratio = 0.6). The 30-day case-fatality rate after first hospital admission was lowest in high-income countries (6.7%), followed by upper-middle-income countries (9.7%), then lower-middle-income countries (21.1%), and highest in low-income countries (31.6%). The proportional risk of death within 30 days of a first hospital admission was 3- to 5-fold higher in lower-middle-income countries and low-income countries compared with high-income countries after adjusting for patient characteristics and use of long-term HF therapies. Conclusions and Relevance: This study of HF patients from 40 different countries and derived from 4 different economic levels demonstrated differences in HF etiologies, management, and outcomes. These data may be useful in planning approaches to improve HF prevention and treatment globally.

Impact of Erg11 Amino Acid Substitutions Identified in Candida auris Clade III Isolates on Triazole Drug Susceptibility.

ERG11 sequencing of 28 Candida auris clade III isolates revealed the presence of concomitant V125A and F126L substitutions. Heterologous expression of Erg11-V125A/F126L in Saccharomyces cerevisiae led to reduced fluconazole and voriconazole susceptibilities. Generation of single substitution gene variants through site-directed mutagenesis uncovered that F126L primarily contributes to the elevated triazole MICs. A similar yet diminished pattern of reduced susceptibility was observed with the long-tailed triazoles posaconazole and itraconazole for the V125A/F126L, F126L, Y132F, and K143R alleles.

Biliary tract cancer.

Biliary tract cancers, including intrahepatic, perihilar, and distal cholangiocarcinoma as well as gallbladder cancer, are low-incidence malignancies in most high-income countries, but represent a major health problem in endemic areas; moreover, the incidence of intrahepatic cholangiocarcinoma is rising globally. Surgery is the cornerstone of cure; the optimal approach depends on the anatomical site of the primary tumour and the best outcomes are achieved through management by specialist multidisciplinary teams. Unfortunately, most patients present with locally advanced or metastatic disease. Most studies in advanced disease have pooled the various subtypes of biliary tract cancer by necessity to achieve adequate sample sizes; however, differences in epidemiology, clinical presentation, natural history, surgical therapy, response to treatment, and prognosis have long been recognised. Additionally, the identification of distinct patient subgroups harbouring unique molecular alterations with corresponding targeted therapies (such as isocitrate dehydrogenase-1 mutations and fibroblast growth factor receptor-2 fusions in intrahepatic cholangiocarcinoma, among others) is changing the treatment paradigm. In this Seminar we present an update of the causes, diagnosis, molecular classification, and treatment of biliary tract cancer.

The clinical landscape of cell-free DNA alterations in 1671 patients with advanced biliary tract cancer.

BACKGROUND: Targeted therapies have transformed clinical management of advanced biliary tract cancer (BTC). Cell-free DNA (cfDNA) analysis is an attractive approach for cancer genomic profiling that overcomes many limitations of traditional tissue-based analysis. We examined cfDNA as a tool to inform clinical management of patients with advanced BTC and generate novel insights into BTC tumor biology. PATIENTS AND METHODS: We analyzed next-generation sequencing data of 2068 cfDNA samples from 1671 patients with advanced BTC generated with Guardant360. We carried out clinical annotation on a multi-institutional subset (n = 225) to assess intra-patient cfDNA-tumor concordance and the association of cfDNA variant allele fraction (VAF) with clinical outcomes. RESULTS: Genetic alterations were detected in cfDNA in 84% of patients, with targetable alterations detected in 44% of patients. Fibroblast growth factor receptor 2 (FGFR2) fusions, isocitrate dehydrogenase 1 (IDH1) mutations, and BRAF V600E were clonal in the majority of cases, affirming these targetable alterations as early driver events in BTC. Concordance between cfDNA and tissue for mutation detection was high for IDH1 mutations (87%) and BRAF V600E (100%), and low for FGFR2 fusions (18%). cfDNA analysis uncovered novel putative mechanisms of resistance to targeted therapies, including mutation of the cysteine residue (FGFR2 C492F) to which covalent FGFR inhibitors bind. High pre-treatment cfDNA VAF was associated with poor prognosis and shorter response to chemotherapy and targeted therapy. Finally, we report the frequency of promising targets in advanced BTC currently under investigation in other advanced solid tumors, including KRAS G12C (1.0%), KRAS G12D (5.1%), PIK3CA mutations (6.8%), and ERBB2 amplifications (4.9%). CONCLUSIONS: These findings from the largest and most comprehensive study to date of cfDNA from patients with advanced BTC highlight the utility of cfDNA analysis in current management of this disease. Characterization of oncogenic drivers and mechanisms of therapeutic resistance in this study will inform drug development efforts to reduce mortality for patients with BTC.

A wearable cardioverter defibrillator with a low false alarm rate.

INTRODUCTION: A wearable cardioverter defibrillator (WCD) is indicated in appropriate patients to reduce the risk for sudden cardiac death. Challenges for patients wearing a WCD have been frequent false shock alarms primarily due to electrocardiogram noise and wear discomfort. The objective of this study was to test a contemporary WCD designed for reduced false shock alarms and improved comfort. METHODS: One hundred and thirty patients with left ventricular ejection fraction ≤40% and an active implantable cardioverter defibrillator (ICD) were fitted with the ASSURE WCD (Kestra Medical Technologies) and followed for 30 days. WCD detection was enabled and shock alarm markers recorded, but shocks and shock alarms were disabled. All WCD episodes and ICD ventricular tachycardia/ventricular fibrillation (VT/VF) episodes were adjudicated. The primary endpoint was the false-positive shock alarm rate with a performance goal of 1 every 3.4 days (0.29 per patient-day). RESULTS: Of 163 WCD episodes, 4 were VT/VF and 159 non-VT/VF (121 rhythms with noise, 32 uncertain with noise, 6 atrial flutter without noise). Only three false-positive shock alarm markers were recorded; one false-positive shock alarm every 1333 patient-days (0.00075 per patient-day, 95% confidence interval: 0.00015-0.00361; p < .001). No ICD recorded VT/VF episodes meeting WCD detection criteria (≥170 bpm for ≥20 s) were missed by the WCD during 3501 patient-days of use. Median wear was 31.0 days (interquartile range [IQR] 2.0) and median daily use 23.0 h (IQR 1.7). Adverse events were mostly mild: skin irritation (19.4%) and musculoskeletal discomfort (8.5%). CONCLUSION: The ASSURE WCD demonstrated a low false-positive shock alarm rate, low patient-reported discomfort, and no serious adverse events.

Paclitaxel chemotherapy disrupts behavioral and molecular circadian clocks in mice.

Cancer patients experience circadian rhythm disruptions in activity cycles and cortisol release that correlate with poor quality of life and decreased long-term survival rates. However, the extent to which chemotherapy contributes to altered circadian rhythms is poorly understood. In the present study, we examined the extent to which paclitaxel, a common chemotherapy drug, altered entrained and free-running circadian rhythms in wheel running behavior, circulating corticosterone, and circadian clock gene expression in the brain and adrenal glands of tumor-free mice. Paclitaxel injections delayed voluntary wheel running activity onset in a light-dark cycle (LD) and lengthened the free-running period of locomotion in constant darkness (DD), indicating an effect on inherent suprachiasmatic nucleus (SCN) pacemaker activity. Paclitaxel attenuated clock gene rhythms in multiple brain regions in LD and DD. Furthermore, paclitaxel disrupted circulating corticosterone rhythms in DD by elevating its levels across a 24-hour cycle, which correlated with blunted amplitudes of Arntl, Nr1d1, Per1, and Star rhythms in the adrenal glands. Paclitaxel also shortened SCN slice rhythms, increased the amplitude of adrenal gland oscillations in PER2::luciferase cultures, and increased the concentration of pro-inflammatory cytokines and chemokines released from the SCN. These findings indicate that paclitaxel disrupts clock genes and behavior driven by the SCN, other brain regions, and adrenal glands, which were associated with chemotherapy-induced inflammation. Together, this preclinical work demonstrates that chemotherapy disrupts both central and peripheral circadian rhythms and supports the possibility that targeted circadian realignment therapies may be a novel and non-invasive way to improve patient outcomes after chemotherapy.

How Broad Should Gram-Negative Coverage Be for Febrile Parenteral Nutrition Dependent Short Bowel Syndrome Patients?

ABSTRACT: Broader spectrum Gram-negative antibiotics are commonly utilized empirically for central line-associated bloodstream infections (CLABSI) in febrile short bowel syndrome (SBS) patients receiving home parenteral nutrition compared to those used empirically for inpatient-acquired CLABSI. This analysis reports 57 CLABSI in 22 patients with SBS admitted from the community and 78 inpatient-acquired CLABSI in 76 patients over a 5-year period. Proportional Gram-negative CLABSI was similar between the SBS and inpatient-acquired cohorts (43.8% vs42.3%, respectively, P  = 0.78). 1.8% and 10.3% (P = 0.125) of Gram-negative CLABSI were non-susceptible to ceftriaxone and 0% and 3.8% (P = 0.52) were non-susceptible to ceftazidime in the SBS and inpatient-acquired cohorts, respectively. In the SBS cohort, home ethanol lock therapy and prior culture results impacted Gramnegative pathogen distribution. Broader empiric Gram-negative coverage for CLABSI among SBS patients compared to inpatients is unnecessary. Third-generation cephalosporins represent appropriate empiric Gramnegative agents for febrile SBS patients presenting from the community to our institution.