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New World screwworm: a re-emerging parasitic threat.

PURPOSE OF REVIEW: New World screwworm (NWS) is an emerging parasitic threat in Central America and Mexico, which is spreading northward into the southern United States. Here we highlight the changing epidemiology, lifecycle of the NWS fly, clinical presentation, identification, treatment, and potential complications of NWS myiasis. RECENT FINDINGS: Despite decades of successfully containing NWS flies south of the Darien Gap in southern Panama, NWS flies reemerged in the Central America region in 2023 and have continued to spread northward ever since. On 3 June 2026, United States Department of Agriculture (USDA) confirmed the identification of an NWS infestation in a young calf in southern Texas. In addition to describing the current epidemiology of the NWS outbreak, we present information about clinical presentation and management of NWS myiasis in patients and include representative cases of patients who experienced NWS myiasis. SUMMARY: This review provides important epidemiologic and clinical updates to an emerging parasitic threat so clinicians can understand the risks and clinical management for patients with suspected NWS myiasis.

Animals

The genomic origins and evolutionary path to a key innovation in the world's most venomous snakes.

Evolutionary innovation is a catalyst for the colonization of new environments and the adaptive radiations of major groups. Novel traits typically evolve through the modification of preexisting characters, but the genetic paths underlying their origin have been challenging to trace, and the general requirements for and relative order of different kinds of gene mutations have been difficult to assess. Here, we trace the genomic origins of four procoagulant venom toxins (factor X, factor V, group I phospholipase A2, and Kunitz-type toxins) that collectively underlie a novel, especially potent blood-clotting venom type in the recently evolved Australian brown snake and taipan clade. We find evidence for a previously unknown fifth toxin, coagulation factor VII, and show that the toxins evolved through two distinct genetic paths. The factor X and factor V toxins evolved through the sequential de novo co-option of ancestral clotting factor proteins that entailed their heterotopic expression in the venom gland, the fixation of segmental duplications containing each locus, and subsequent gain-of-function mutations that rendered factor X and factor V constitutively active. In contrast, the phospholipase A2 and Kunitz-type toxins evolved by modifying the functions of neurotoxins that were part of the venom arsenal. Our findings support models in which innovative mutations in single-copy genes precede gene duplication in the evolution of novel proteins and offer a rare view into the genesis of a complex trait that has played a central role in a major adaptive radiation.

Animals

Evidence of genome-wide relaxed selection on mildly deleterious mutations in an ancient subterranean catfish.

About one hundred subterranean catfish species have been described, resulting from repeated colonization of cave environments by multiple surface lineages. Most cave-dwelling species are found in the Americas, in particular in South America, but a few species also live in Central and North America. Despite the availability of high-quality genome assemblies for two cave species, the Mexican blind catfish Prietella phreatophila and the Colombian blind catfish Trichomycterus rosablanca, genomic approaches to investigate genetic changes associated with subterranean life or to estimate cave colonization times remain largely unexplored. To fill this gap, we additionally sequenced the genomes of four blind and depigmented subterranean catfishes from Peru (three Trichomycterus and one Astroblepus), as well as the genomes of four close surface relatives. We first extracted a large set of light-related genes, such as phototransduction and crystallin genes, and found contrasting decays of these sequences in different cave species, from 1% of pseudogenes in T. rosablanca to 48% in P. phreatophila. Two independent molecular dating methods gave congruent ages, indicating that these catfishes colonized subterranean habitats at different times, ranging from Early Pliocene to Late Pleistocene, supporting the hypothesis that surface catfishes repeatedly and rapidly adapted to subterranean habitats. The oldest cave species, P. phreatophila, appears to have been thriving in the dark for over 3.5 million years. Moreover, a genome-wide analysis of protein-coding genes suggests weaker purifying selection on mildly deleterious mutations in this cavefish than in other catfish lineages, likely reflecting a long-term small effective population size.

cavefishes

Substance use and co-occurring mental health conditions among adolescents and young adults in North America: a systematic review.

BACKGROUND: Substance use and co-occurring mental health conditions are common among adolescents and young adults and represent an important clinical and public health concern in North America. Trauma exposure, psychiatric symptoms, and social adversity frequently co-occur with substance-related problems in this population. This systematic review aimed to synthesize evidence on prevalence patterns, associated clinical and psychosocial factors, and care-related implications described in the literature on adolescents and young adults with substance use and co-occurring mental health conditions. METHODS: This systematic review followed PRISMA guidelines and was preregistered in PROSPERO (CRD42024581685). A systematic search was conducted in MEDLINE (Ovid), Embase, PsycINFO, and Google Scholar. Eligible studies examined adolescents and young adults (≤ 25 years) in North America. A combination of subject headings, keywords, and synonyms for the concepts "adolescents," "young adults," "substance use disorders," and "co-occurring mental health conditions" was used. Of 1,882 records identified, 29 studies met the inclusion criteria. Given the heterogeneity of the literature, findings were synthesized narratively. RESULTS: The included studies showed heterogeneity in population, setting, denominator, and ascertainment method. Across the literature, depressive, anxiety-related, trauma-related, and externalizing mental health presentations were frequently reported alongside substance-related problems in adolescents and young adults. Trauma exposure, adverse childhood experiences, and broader social adversity were also commonly reported in association with substance-related problems across studies. Care-related implications were more limited and were largely derived as future directions mentioned across studies rather than direct evaluations of youth-specific service models. CONCLUSION: Co-occurring mental health and substance-related problems were frequently reported among adolescents and young adults in high-risk and service-engaged populations in North America. Trauma and social adversity were prominent across the reviewed literature, while direct evidence for evaluated, integrated, youth-specific care models remains limited. These findings support the relevance of developmentally appropriate, integrated, and trauma-informed approaches to care and highlight the need for further research directly evaluating improved service delivery models for this population. CLINICAL TRIAL NUMBER: Not applicable.

Humans

A Duty to Act.

Explore the source record for details and available documents.

healthcare

Spironolactone, early acute eGFR changes, and clinical outcomes in patients with heart failure with preserved ejection fraction: insights from TOPCAT Americas.

AIMS: Early acute changes in estimated glomerular filtration rate (eGFR) have been well described with renin-angiotensin system inhibitors and sodium-glucose cotransporter-2 inhibitors, but less is known about the frequency, prognostic relevance, and implications of these changes after mineralocorticoid receptor antagonist (MRA) initiation in patients with heart failure with preserved ejection fraction (HFpEF). METHODS: We performed a post-hoc analysis of 1648 patients enrolled in the TOPCAT trial (Americas regional subgroup), defining an early eGFR dip as a ≥15% decrease in eGFR between baseline and week 4. Landmark analyses assessed the association of eGFR changes, treatment, and the primary composite endpoint (cardiovascular death, HF hospitalization, or aborted cardiac arrest). RESULTS: Within 4 weeks of treatment initiation, 431 (26%) patients experienced acute eGFR decrease with a higher proportion of patients assigned to spironolactone [269 (33%)] compared with placebo [162 (20%)] (odds ratio 1.97; 95% confidence interval 1.58-2.47). An acute eGFR decrease was independently associated with higher risk of subsequent cardiovascular outcomes, irrespective of treatment arm. However, treatment with spironolactone appeared beneficial in reducing the primary cardiovascular outcome irrespective of the presence [hazard ratio 0.75 (0.53-1.08)] or absence [0.80 (0.64-1.00)] of early eGFR decrease (Pinteraction = .81). At any given magnitude of eGFR decline, risk of the primary endpoint was consistently lower with spironolactone compared with placebo (Pinteraction = .64). CONCLUSIONS: Early acute eGFR changes were common and adversely prognostic in patients with HFpEF. Spironolactone treatment was beneficial in improving cardiovascular outcomes, despite a modest increase in the likelihood of acute eGFR decrease. An acute eGFR decrease early after MRA initiation should not automatically prompt treatment discontinuation. TRIAL REGISTRATION: ClinicalTrials.gov NCT00094302.

Humans

Precision Oncology in Hepatopancreatobiliary Cancer Surgery.

Advances in technology have allowed for the characterization of tumors at the genomic, transcriptomic, and proteomic levels. There are well-established targets for biliary tract cancers, with exciting new targets emerging in pancreatic ductal adenocarcinoma and potential targets in hepatocellular carcinoma. Taken together, these data suggest an important role for molecular profiling for personalizing cancer therapy in advanced disease and need for design of novel neoadjuvant studies to leverage these novel therapeutics perioperatively in the surgical patient.

Humans

Advanced/Novel Stenting for Pediatric Dynamic Airway Collapse.

Pediatric dynamic airway collapse is a complex condition that can impact all levels of the pediatric airway. These conditions can pose life threatening risk to pediatric patients and carry lasting impacts. While traditionally, tracheostomy has been used to address all levels of dynamic collapse, recent advances have allowed for more individualized, anatomy-specific stenting and splinting strategies for treatment. This article covers pathophysiology and the latest evidence on strategies to address nasopharyngeal, oropharyngeal, proximal trachea, and tracheobronchial dynamic collapse.

Humans

Congenital Laryngomalacia: Pathophysiology, Clinical Spectrum, and Holistic Management.

Congenital laryngomalacia is the most common cause of infant stridor and arises from interacting structural, neuromuscular, and inflammatory mechanisms that produce dynamic supraglottic collapse. Disease severity spans mild stridor to significant obstruction, aspiration, and failure to thrive, often influenced by comorbid medical conditions. Diagnosis relies on flexible laryngoscopy supported by instrumental swallowing studies and microdirect laryngoscopy and bronchoscopy when indicated. Most infants respond to conservative management, particularly targeted feeding modifications, while acid suppression offers benefit in selective cases. Supraglottoplasty provides effective, durable improvement for severe disease and significantly enhances infant outcomes and family quality of life.

Humans

Evolution of Precision Oncology, Personalized Medicine, and Molecular Tumor Boards.

With multiple molecular targeted therapies available for patients with cancer that correspond to a specific genetic alteration, the selection of the best treatment is essential to ensure therapeutic efficacy. Molecular tumor boards (MTBs) play a key role in this process to deliver personalized medicine to patients with cancer in a multidisciplinary manner. Historically, personalized medicine has been offered to patients with advanced cancer, but the incorporation of molecular targeted therapies and immunotherapy into the perioperative setting requires clinicians to understand the role of the MTB. Evidence is accumulating to support feasibility and survival benefit in patients treated with matched therapy.

Humans

Cost-Effectiveness and the Economics of Genomic Testing and Molecularly Matched Therapies.

Cost-effectiveness analysis of precision oncology can help guide value-driven care. Next-generation sequencing is increasingly cost-efficient over single gene testing because diagnostic algorithms require multiple individual gene tests to determine biomarker status. Matched targeted therapy is often not cost-effective due to the high cost associated with drug treatment. However, genomic profiling can promote cost-effective care by identifying patients who are unlikely to benefit from therapy. Additional applications of genomic profiling such as universal testing for hereditary cancer syndromes and germline testing in patients with cancer may represent cost-effective approaches compared with traditional history-based diagnostic methods.

Humans

Transverse Tibial Transport for Limb Salvage in Ischemic Lower Extremity Disease: Technique, Mechanisms, and Clinical Outcomes-A Systematic Review.

Transverse tibial transport (TTT) is a surgical technique derived from Ilizarov's distraction osteogenesis principles that stimulates angiogenesis and microcirculatory regeneration in the ischemic lower limb without directly manipulating macrovascular anatomy. By creating a proximal tibial cortical bone window and distracting it transversely using an external fixator, TTT triggers converging cascades of growth factor release, endothelial progenitor cell mobilization, and immunomodulation that translate into improved distal limb perfusion and wound healing. Combined TTT plus endovascular therapy improves amputation-free survival versus endovascular therapy alone. Prospective randomized trials and standardized international protocols are needed to consolidate TTT's role in multidisciplinary limb salvage pathways.

Humans

Pervasive hybridization and introgression in Diervilleae (Caprifoliaceae).

Diervilleae (Caprifoliaceae) is a horticulturally important lineage with striking floral diversity and a long history of interspecific crossing, suggesting reticulate evolution. We integrated nuclear SNPs and whole plastome data to reconstruct a phylogenomic backbone for the tribe and to identify hybrids, cultivated accessions, and introgression among lineages. Nuclear and plastid phylogenies consistently recover Weigela and Diervilla as reciprocally monophyletic and resolve four major lineages within Weigela, providing a reproducible framework for revising sectional limits and species boundaries. Cultivated accessions form a well supported clade sister to W. florida and show predominantly W. florida ancestry while retaining contributions from multiple wild lineages, consistent with recurrent crossing, backcrossing, and selection. Analyses of wild populations reveal recurrent hybrids and enable plausible parental combinations to be inferred. Tests across the genome further indicate strong evidence for historical introgression across Diervilleae, with the strongest signals involving W. middendorffiana, W. maximowiczii, and Diervilla. Fossil evidence, divergence time estimation, and paleodistribution modelling together suggest range expansion during the Miocene and Pliocene followed by climate driven contraction, providing a spatiotemporal context for episodic contact, introgression, and the East Asia-North America disjunction.

Hybridization, Genetic

Editorial Commentary: Stiff Patients After Rotator Cuff Repair: How Many Had Underrecognized Preoperative Adhesive Capsulitis?

Stiffness after rotator cuff repair is one of the most common sources of disability and one of the most common complications. Smoking, diabetes, Workers' compensation status, and traumatic tears are among the strongest risk factors. This is important information in setting appropriate expectations for both the patient and the surgeon preoperatively. Some of these factors are also associated with preoperative stiffness, so surgeons should maintain a high index of suspicion for concomitant adhesive capsulitis in patients presenting with limited motion, particularly in diabetic and non-English speaking populations. In cases where both a rotator cuff tear and adhesive capsulitis coexist, performing a concurrent capsular release or manipulation during the index procedure may improve functional outcomes and reduce the necessity for secondary surgical intervention.

Humans

Alternative genetic codes in bacteria and archaea identified with a fast k-mer-based algorithm.

The genetic code is conserved across all domains of life and is often described as universal. Nevertheless, many exceptions to the "universal" code have now been documented, most of these through manual or semiautomated inspection of highly conserved genes. Modern bioinformatics tools improved our ability to find alternative genetic codes but remain computationally expensive, preventing widespread use on thousands of new species identified by sequencing environmental samples. Here, I report a >100-fold accelerated method for inferring the genetic code directly from assembled genomes and apply it to thousands of previously uncharacterized assemblies from archaea and bacteria. I describe three candidate genetic code variations, one of which, an alternative genetic code used by a family of Asgard archaea, is a unique example of sense codon reassignments for this domain. Identifying genetic code variations is important for understanding evolution of the standard code and improving accuracy of protein databases and open reading frame identification.

Genetic Code

In vivo genome-wide CRISPR screens identify FOXR1 as a suppressor of CD8+ T cell antitumor immunity.

T cell dysfunction critically limits the efficacy of T cell-based immunotherapies in solid tumors, yet the intrinsic regulators of T cell dysfunction remain incompletely understood. Through an in vivo genome-wide CRISPR screen in tumor-infiltrating CD8+ T cells, we identified Forkhead Box R1 (FOXR1) as a potent transcriptional suppressor of CD8+ T cell effector functions. Genetic ablation of FOXR1 significantly enhanced cytokine production and cytotoxic capacity in both murine and human CD8+ T cells, whereas its overexpression impaired T cell activation and effector molecule expression. Mechanistically, multiomics integration of RNA-seq, CUT&Tag-seq, and ATAC-seq revealed that FOXR1 binds directly to promoter regions of key effector genes, including IL2, GZMB, and PRF1, and represses their expression. Importantly, FOXR1 deletion in human anti-CD19 CAR T cells improved their efficacy against solid tumors, demonstrating that FOXR1 is a checkpoint of T cell effector function and targeting FOXR1 is a promising strategy to enhance CAR T cell efficacy against solid tumors.

Animals

Cryo-EM structure of TGFBIp fibrils driven by a corneal dystrophy-linked mutation enables design of peptide inhibitors of aggregation.

Corneal dystrophy is a heterogeneous group of diseases which manifests clinically by progressive corneal opacity and diminishing visual acuity. A group of corneal dystrophies are linked to autosomal dominant mutations in transforming growth factor β-induced protein (TGFBIp) and characterized by extracellular amyloid-positive deposits of unknown molecular structure. Here, we determined the cryogenic-electron microscopy (cryo-EM) structure of amyloid fibrils formed by the TGFBIp FAS1-4 domain with corneal dystrophy-linked mutation V624M. The L569 to N609 fibril core, which includes the Y571-R588 segment enriched in patient corneal deposits, forms symmetrical protofilaments with internal solvent channels. Leveraging this structure, we designed peptide inhibitors intended to bind onto fibril ends to block elongation, targeting the unequal growth of symmetrical protofilaments. Our G1 and H4 inhibitors exhibit concentration-dependent reduction of TGFBIp FAS1-4 aggregation as assessed by Thioflavin T, solubility fractionation, and electron microscopy. Our work illustrates how fibril structures can guide rational inhibitor design and suggests the targeting of protein aggregates as a therapeutic approach for corneal and ocular diseases.

betaIG-H3 Protein