Prescription Digital Therapeutics for Substance Use Disorder in Primary Care: Mixed Methods Evaluation of a Pilot Implementation Study.

BACKGROUND: Delivering prescription digital therapeutics (ie, evidence-based interventions designed to treat, manage, or prevent disorders via websites or smartphone apps) in primary care could increase patient access to substance use disorder (SUD) treatments. However, the optimal approach to implementing prescription digital therapeutics in primary care remains unknown. OBJECTIVE: This pilot study is a precursor to a larger trial designed to test whether implementation strategies (practice facilitation [PF] and health coaching [HC]) improve the delivery of prescription digital therapeutics for SUDs in primary care. This mixed methods study describes outcomes among patients in the 2 pilot clinics and presents qualitative findings on implementation. METHODS: From February 10 to August 6, 2021, a total of 3 mental health specialists embedded in 2 primary care practices of the same integrated health system were tasked with offering app-based prescription digital therapeutics to patients with SUD. In the first half of the pilot, implementation activities included training and supportive tools. PF (at 1 clinic) and HC (at 2 clinics) were added in the second half. All study analyses relied on secondary data, including electronic health records and digital therapeutic vendor data. Primary outcomes were the proportion of patients reached by the prescription digital therapeutics and fidelity related to ideal use. We used qualitative methods to assess the adherence to planned activities and the barriers and facilitators to implementing prescription digital therapeutics. RESULTS: Of all 18 patients prescribed the apps, 10 (56%) downloaded the app and activated their prescription, and 8 (44%) completed at least 1 module of content. Patients who activated the app completed 1 module per week on average. Ideal use (fidelity) was defined as completing 4 modules per week and having a monthly SUD-related visit; 1 (6%) patient met these criteria for 10 weeks (of the 12-week prescription period). A total of 5 (28%) patients had prescriptions while HC was available, 2 (11%) were successfully contacted, and both declined coaching. Clinicians reported competing clinical priorities, technical challenges, and logistically complex workflows in part because the apps required a prescription. Some pilot activities were impacted by staff turnover that coincided with the COVID-19 pandemic. The facilitators to implementation were high engagement and the perception that the apps could meet patient needs. CONCLUSIONS: The pilot study encountered the barriers to implementing prescription digital therapeutics in a real-world primary care setting, especially staffing shortages, turnover, and competing priorities for clinic teams. The larger randomized trial will clarify the extent to which PF and HC improve the implementation of digital therapeutics. TRIAL REGISTRATION: ClinicalTrials.gov NCT04907045; https://clinicaltrials.gov/study/NCT04907045.

A Transmit-Receive Phased Array for Microbubble-Mediated Focused Ultrasound Brain Therapy in Small Animals.

Focused ultrasound (FUS) combined with circulating microbubbles (MBs) can be employed for non-invasive, localized agent delivery across the blood-brain barrier (BBB). Previous work has demonstrated the feasibility of clinical-scale transmit-receive phased arrays for performing transcranial therapies under MB imaging feedback. OBJECTIVE: This study aimed to design, construct, and evaluate a dual-mode phased array for MB-mediated FUS brain therapy in small animals. METHODS: A 256-element sparse hemispherical array (100 mm diameter) was fabricated by installing 128 PZT cylinder transmitters (f0 = 1.16 MHz) and 128 broadband PVDF receivers within a 3D-printed scaffold. RESULTS: The transmit array's focal size at the geometric focus was 0.8 mm × 0.8 mm × 1.7 mm, with a 31 mm/27 mm (lateral/axial) steering range. The receive array's point spread function was 0.6 mm × 0.6 mm × 1.5 mm (1.16 MHz source) at the geometric focus, and sources were localized up to 30 mm/16 mm (lateral/axial) from geometric focus. The array was able to spatially map MB cloud activity in 3D throughout a vessel-mimicking phantom at sub-, ultra-, and second-harmonic frequencies. Preliminary in-vivo work demonstrated its ability to induce localized BBB permeability changes under 3D sub-harmonic MB imaging feedback in a mouse model. CONCLUSION: Small form factor transmit-receive phased arrays enable acoustic imaging-controlled FUS and MB-mediated brain therapies with high targeting precision required for rodent studies. SIGNIFICANCE: Dual-mode phased arrays dedicated for small animal use will facilitate high-throughput studies of FUS-mediated BBB permeability enhancement to explore novel therapeutic strategies for future clinical application.

Extragustatory bitter taste receptors in head and neck health and disease.

Taste receptors, first described for their gustatory functions within the oral cavity and oropharynx, are now known to be expressed in many organ systems. Even intraoral taste receptors regulate non-sensory pathways, and recent literature has connected bitter taste receptors to various states of health and disease. These extragustatory pathways involve previously unexplored, clinically relevant roles for taste signaling in areas including susceptibility to infection, antibiotic efficacy, and cancer outcomes. Among other physicians, otolaryngologists who manage head and neck diseases should be aware of this growing body of evidence and its relevance to their fields. In this review, we describe the role of extragustatory taste receptors in head and neck health and disease, highlighting recent advances, clinical implications, and directions for future investigation. Additionally, this review will discuss known TAS2R polymorphisms and the associated implications for clinical prognosis.

Case report: Longitudinal evaluation and treatment of a melanoma-associated retinopathy patient.

Melanoma-associated retinopathy (MAR) is a paraneoplastic syndrome associated with cutaneous metastatic melanoma in which patients develop vision deficits that include reduced night vision, poor contrast sensitivity, and photopsia. MAR is caused by autoantibodies targeting TRPM1, an ion channel found in melanocytes and retinal ON-bipolar cells (ON-BCs). The visual symptoms arise when TRPM1 autoantibodies enter ON-BCs and block the function of TRPM1, thus detection of TRPM1 autoantibodies in patient serum is a key criterion in diagnosing MAR. Electroretinograms are used to measure the impact of TRPM1 autoantibodies on ON-BC function and represent another important diagnostic tool for MAR. To date, MAR case reports have included one or both diagnostic components, but only for a single time point in the course of a patient's disease. Here, we report a case of MAR supported by longitudinal analysis of serum autoantibody detection, visual function, ocular inflammation, vascular integrity, and response to slow-release intraocular corticosteroids. Integrating these data with the patient's oncological and ophthalmological records reveals novel insights regarding MAR pathogenesis, progression, and treatment, which may inform new research and expand our collective understanding of the disease. In brief, we find TRPM1 autoantibodies can disrupt vision even when serum levels are barely detectable by western blot and immunohistochemistry; intraocular dexamethasone treatment alleviates MAR visual symptoms despite high levels of circulating TRPM1 autoantibodies, implicating antibody access to the retina as a key factor in MAR pathogenesis. Elevated inflammatory cytokine levels in the patient's eyes may be responsible for the observed damage to the blood-retinal barrier and subsequent entry of autoantibodies into the retina.

Intragenic DNA inversions expand bacterial coding capacity.

Bacterial populations that originate from a single bacterium are not strictly clonal and often contain subgroups with distinct phenotypes1. Bacteria can generate heterogeneity through phase variation-a preprogrammed, reversible mechanism that alters gene expression levels across a population1. One well-studied type of phase variation involves enzyme-mediated inversion of specific regions of genomic DNA2. Frequently, these DNA inversions flip the orientation of promoters, turning transcription of adjacent coding regions on or off2. Through this mechanism, inversion can affect fitness, survival or group dynamics3,4. Here, we describe the development of PhaVa, a computational tool that identifies DNA inversions using long-read datasets. We also identify 372 'intragenic invertons', a novel class of DNA inversions found entirely within genes, in genomes of bacterial and archaeal isolates. Intragenic invertons allow a gene to encode two or more versions of a protein by flipping a DNA sequence within the coding region, thereby increasing coding capacity without increasing genome size. We validate ten intragenic invertons in the gut commensal Bacteroides thetaiotaomicron, and experimentally characterize an intragenic inverton in the thiamine biosynthesis gene thiC.

Photosensitized Oxidative Damage from a New Perspective: The Influence of Before-Light and After-Light Reaction Conditions.

Photooxidative damage is heavily influenced by the presence of bioactive agents. Conversely, bioactive agents influence the local environment, which in turn is perturbed by photooxidative damage. These sorts of processes give rise to a version of the "chicken-and-egg" quandary. In this Perspective, we probe this issue by referring to photooxidative damage in one direction as the light-dark (L-D) sequence and in a second direction as the dark-light (D-L) sequence with a reversed cause and effect. The L-D sequence can lead to the downstream production of reactive molecular species (RMS) in the dark, whereas the D-L sequence can be a pre-irradiation period, such as an additive to limit cellular iron levels to enhance biosynthesized amounts of a protoporphyrin sensitizer. A third direction comes from L-D or D-L sequences, or both simultaneously, which can also be useful for optimizing photodynamics. Photodynamic optimization will benefit from understanding and quantitating unidirectional L-D and D-L pathways, and bidirectional L-D/D-L pathways, for improved control over photooxidative damage. Photooxidative damage, which occurs during anticancer photodynamic therapy (PDT), will be shown to involve RMS. Such RMS include persulfoxides (R2S+OO-), NO2•, peroxynitrate (O2NOO-), OOSCN-, SO3•-, selenocyanogen [(SeCN)2], the triselenocyanate anion [(SeCN)3-], I•, I2•-, I3-, and HOOI, as well as additives to destabilize membranes (e.g., caspofungin and saponin A16), inhibit DNA synthesis (5-fluorouracil), or sequester iron (desferrioxamine). In view of the success that additive natural products and repurposed drugs have had in PDT, a Perspective of additive types is expected to reveal mechanistic details for enhanced photooxidation reactions in general. Indeed, strategies for how to potentiate photooxidations with additives remain highly underexplored.

Author Correction: Everyday Uses of Music Listening and Music Technologies by Caregivers and People With Dementia: Survey and Focus Group Study.

[This corrects the article DOI: 10.2196/54186.].

Human cells contain myriad excised linear intron RNAs with links to gene regulation and potential utility as biomarkers.

A previous study using Thermostable Group II Intron Reverse Transcriptase sequencing (TGIRT-seq) found human plasma contains short (≤300 nt) structured full-length excised linear intron (FLEXI) RNAs with potential to serve as blood-based biomarkers. Here, TGIRT-seq identified >9,000 different FLEXI RNAs in human cell lines, including relatively abundant FLEXIs with cell-type-specific expression patterns. Analysis of public CLIP-seq datasets identified 126 RNA-binding proteins (RBPs) that have binding sites within the region corresponding to the FLEXI or overlapping FLEXI splice sites in pre-mRNAs, including 53 RBPs with binding sites for ≥30 different FLEXIs. These included splicing factors, transcription factors, a chromatin remodeling protein, cellular growth regulators, and proteins with cytoplasmic functions. Analysis of ENCODE datasets identified subsets of these RBPs whose knockdown impacted FLEXI host gene mRNA levels or proximate alternative splicing, indicating functional interactions. Hierarchical clustering identified six subsets of RBPs whose FLEXI binding sites were co-enriched in six subsets of functionally related host genes: AGO1-4 and DICER, including but not limited to agotrons or mirtron pre-miRNAs; DKC1, NOLC1, SMNDC1, and AATF (Apoptosis Antagonizing Transcription Factor), including but not limited to snoRNA-encoding FLEXIs; two subsets of alternative splicing factors; and two subsets that included RBPs with cytoplasmic functions (e.g., LARP4, PABPC4, METAP2, and ZNF622) together with regulatory proteins. Cell fractionation experiments showed cytoplasmic enrichment of FLEXI RNAs with binding sites for RBPs with cytoplasmic functions. The subsets of host genes encoding FLEXIs with binding sites for different subsets of RBPs were co-enriched with non-FLEXI other short and long introns with binding sites for the same RBPs, suggesting overarching mechanisms for coordinately regulating expression of functionally related genes. Our findings identify FLEXIs as a previously unrecognized large class of cellular RNAs and provide a comprehensive roadmap for further analyzing their biological functions and the relationship of their RBPs to cellular regulatory mechanisms.

Photochemical phosphorus-enabled scaffold remodeling of carboxylic acids.

The excitation of carbonyl compounds by light to generate radical intermediates has historically been restricted to ketones and aldehydes; carboxylic acids have been overlooked because of high energy requirements and low quantum efficiency. A successful activation strategy would necessitate a bathochromic shift in the absorbance profile, an increase in triplet diradical lifetime, and ease of further functionalization. We present a single-flask transformation of carboxylic acids to acyl phosphonates that can access synthetically useful triplet diradicals under visible light or near-ultraviolet irradiation. The use of phosphorus circumvents unproductive Norrish type I processes, promoting selectivity that enables hydrogen-atom transfer reactivity. Use of this strategy promotes the efficient scaffold remodeling of carboxylic acids through various annulation, contraction, and expansion manifolds.

Impact of catastrophic brain injury guidelines on organ donation rates: Results of an EAST multicenter trial.

BACKGROUND: One third of organ donors suffer catastrophic brain injury (CBI). There are no standard guidelines for the management of traumatic CBI prior to brain death, and not all trauma centers have institutional CBI guidelines. In addition, there is high variability in management between institutions with guidelines. Catastrophic brain injury guidelines vary and may include various combinations of hormone therapy, vasopressors, fluid resuscitation, and other practices. We hypothesized that centers with CBI guidelines have higher organ donation rates than those without. METHODS: This prospective, observational EAST-sponsored multicenter trial included adult (18+ years old) traumatic-mechanism CBI patients at 33 level I and II trauma centers from January 2022 to May 2023. Catastrophic brain injury was defined as a brain injury causing loss of function above the brain stem and subsequent death. Cluster analysis with linear mixed-effects model including UNOS regions and hospital size by bed count was used to determine whether CBI guidelines are associated with organ donation. RESULTS: A total of 790 CBI patients were included in this analysis. In unadjusted comparison, CBI guideline centers had higher rates of organ donation and use of steroids, whole blood, and hormone therapy. In a linear mixed-effects model, CBI guidelines were not associated with organ donation. Registered organ donor status, steroid hormones, and vasopressin were associated with increased relative risk of donation. CONCLUSION: There is high variability in management of CBI, even at centers with CBI guidelines in place. While the use of institutional CBI guidelines was not associated with increased organ donation, guidelines in this study were not identical. Hormone replacement with steroids and vasopressin was associated with increased donation. Hormone resuscitation is a common feature of CBI guidelines. Further analysis of individual practices that increase organ donation after CBI may allow for more effective guidelines and an overall increase in donation to decrease the long waiting periods for organ transplant recipients. LEVEL OF EVIDENCE: Prognostic; Level III.

Wearable magnetoencephalography in a lightly shielded environment.

Wearable magnetoencephalography based on optically pumped magnetometers (OPM-MEG) offers non-invasive and high-fidelity measurement of human brain electrophysiology. The flexibility of OPM-MEG also means it can be deployed in participants of all ages and permits scanning during movement. However, the magnetic fields generated by neuronal currents - which form the basis of the OPM-MEG signal - are much smaller than environmental fields, and this means measurements are highly sensitive to interference. Further, OPMs have a low dynamic range, and should be operated in near-zero background field. Scanners must therefore be housed in specialised magnetically shielded rooms (MSRs), formed from multiple layers of shielding material. The MSR is a critical component, and current OPM-optimised shields are large (>3 m in height), heavy (>10,000 kg) and expensive (with up to 5 layers of material). This restricts the uptake of OPM-MEG technology. Here, we show that the application of the Maxwell filtering techniques signal space separation (SSS) and its spatiotemporal extension (tSSS) to OPM-MEG data can isolate small signals of interest measured in the presence of large interference. We compare phantom recordings and MEG data from a participant performing a motor task in a state-of-the-art 5-layer MSR, to similar data collected in a lightly shielded room: application of tSSS to data recorded in the lightly shielded room allowed accurate localisation of a dipole source in the phantom and neuronal sources in the brain. Our results point to future deployment of OPM-MEG in lighter, cheaper and easier-to-site MSRs which could catalyse widespread adoption of the technology.

A novel technique for skull base reconstruction in craniofacial fibrous dysplasia surgery using three-dimensional printing and a dental alginate mold: illustrative case.

BACKGROUND: Fibrous dysplasia is a rare and benign skeletal lesion characterized by fibrous tissue proliferation due to an abnormal osteogenesis replacing normal bone. OBSERVATIONS: An 18-year-old male with fibrous dysplasia of the left sphenoid, ethmoid, orbit, and frontal bones was managed with excision and skull base reconstruction. After complete removal of the tumor, skull base reconstruction was commenced by making a reverse temporalis flap and placing it over the opened paranasal sinuses for a robust vascularized graft, followed by an abdominal fat graft, and then a pedicled pericranal flap was added to complete the multilayer onlay graft. To recreate the skull base, a mirror image of the contralateral skull base was constructed using three-dimensional (3D) printing, and the 3D-printed model was sterilized prior to the surgery. Intraoperatively, the model was then pressed onto dental alginate gel to make a negative mold. This was used to make the definitive flap using polymethylmethacrylate. Temporoplasty was also performed using polymethylmethacrylate to fill the defect left by the temporalis graft. The patient recovered well following the procedure. LESSONS: Appropriate, personalized skull base reconstruction techniques can be successfully done with 3D printing using alternative low-cost materials and implements, especially following resection of cases like craniofacial fibrous dysplasia. https://thejns.org/doi/10.3171/CASE24262.

Biochemical characterization of Mycobacterial RNA polymerases.

Tuberculosis is caused by the bacterium Mycobacterium tuberculosis (Mtb). While eukaryotic species employ several specialized RNA polymerases (Pols) to fulfill the RNA synthesis requirements of the cell, bacterial species use a single RNA polymerase (RNAP). To contribute to the foundational understanding of how Mtb and the related non-pathogenic mycobacterial species, Mycobacterium smegmatis (Msm), perform the essential function of RNA synthesis, we performed a series of in vitro transcription experiments to define the unique enzymatic properties of Mtb and Msm RNAPs. In this study, we characterize the mechanism of nucleotide addition used by these bacterial RNAPs with comparisons to previously characterized eukaryotic Pols I, II, and III. We show that Mtb RNAP and Msm RNAP demonstrate similar enzymatic properties and nucleotide addition kinetics to each other but diverge significantly from eukaryotic Pols. We also show that Mtb RNAP and Msm RNAP uniquely bind a nucleotide analog with significantly higher affinity than canonical nucleotides, in contrast to eukaryotic RNA polymerase II. This affinity for analogs may reveal a vulnerability for selective inhibition of the pathogenic bacterial enzyme.IMPORTANCETuberculosis, caused by the bacterium Mycobacterium tuberculosis (Mtb), remains a severe global health threat. The World Health Organization (WHO) has reported that tuberculosis is second only to COVID-19 as the most lethal infection worldwide, with more annual deaths than HIV and AIDS (WHO.int). The first-line treatment for tuberculosis, Rifampin (or Rifampicin), specifically targets the Mtb RNA polymerase. This drug has been used for decades, leading to increased numbers of multi-drug-resistant infections (Stephanie, et al). To effectively treat tuberculosis, there is an urgent need for new therapeutics that selectively target vulnerabilities of the bacteria and not the host. Characterization of the differences between Mtb enzymes and host enzymes is critical to inform these ongoing drug design efforts.

Structural basis for adhesin secretion by the outer-membrane usher in type 1 pili.

Gram-negative bacteria produce chaperone-usher pathway pili, which are extracellular protein fibers tipped with an adhesive protein that binds to a receptor with stereochemical specificity to determine host and tissue tropism. The outer-membrane usher protein, together with a periplasmic chaperone, assembles thousands of pilin subunits into a highly ordered pilus fiber. The tip adhesin in complex with its cognate chaperone activates the usher to allow extrusion across the outer membrane. The structural requirements to translocate the adhesin through the usher pore from the periplasm to the extracellular space remains incompletely understood. Here, we present a cryoelectron microscopy structure of a quaternary tip complex in the type 1 pilus system from Escherichia coli, which consists of the usher FimD, chaperone FimC, adhesin FimH, and the tip adapter FimF. In this structure, the usher FimD is caught in the act of secreting its cognate adhesin FimH. Comparison with previous structures depicting the adhesin either first entering or having completely exited the usher pore reveals remarkable structural plasticity of the two-domain adhesin during translocation. Moreover, a piliation assay demonstrated that the structural plasticity, enabled by a flexible linker between the two domains, is a prerequisite for adhesin translocation through the usher pore and thus pilus biogenesis. Overall, this study provides molecular details of adhesin translocation across the outer membrane and elucidates a unique conformational state adopted by the adhesin during stepwise secretion through the usher pore. This study elucidates fundamental aspects of FimH and usher dynamics critical in urinary tract infections and is leading to antibiotic-sparing therapeutics.

Control of hyperpnoea and pulmonary gas exchange during prolonged exercise: The role of group III/IV muscle afferent feedback.

It remains unclear whether feedback from group III/IV muscle afferents is of continuous significance for regulating the pulmonary response during prolonged (>5 min), steady-state exercise. To elucidate the influence of these sensory neurons on hyperpnoea, gas exchange efficiency, arterial oxygenation and acid-base balance during prolonged locomotor exercise, 13 healthy participants (4 females; 21 (3) years, V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ : 46 (8) ml/kg/min) performed consecutive constant-load cycling bouts at ∼50% (20 min), ∼75% (20 min) and ∼100% (5 min) of V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ with intact (CTRL) and pharmacologically attenuated (lumbar intrathecal fentanyl; FENT) group III/IV muscle afferent feedback from the legs. Pulmonary responses were continuously recorded and arterial blood (radial catheter) periodically collected throughout the exercise. Pulmonary gas exchange efficiency was evaluated using the alveolar-arterial P O 2 ${{P}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ difference ( A - a D O 2 ${\mathrm{A - a}}{{D}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ ). There were no differences in any of the variables of interest between conditions before the start of the exercise. Pulmonary ventilation was up to 20% lower across all intensities during FENT compared to CTRL exercise (P < 0.001) and this hypoventilation was accompanied by an up to 10% lower arterial P O 2 ${{P}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ and a 2-4 mmHg higher P C O 2 ${{P}_{{\mathrm{C}}{{{\mathrm{O}}}_{\mathrm{2}}}}}$ (both P < 0.001). The exercise-induced widening of A - a D O 2 ${\mathrm{A - a}}{{D}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ was up to 25% larger during FENT compared to CTRL (P < 0.001). Importantly, the differences developed within the first minute of each stage and persisted, or further increased, throughout the remainder of each bout. These findings reflect a critical and time-independent significance of feedback from group III/IV leg muscle afferents for continuously regulating the ventilatory response, gas exchange efficiency, arterial oxygenation and acid-base balance during human locomotion. KEY POINTS: Feedback from group III/IV leg muscle afferents reflexly contributes to hyperpnoea during short duration (i.e. <5 min) locomotor exercise. Whether continuous feedback from these sensory neurons is obligatory to ensure adequate pulmonary responses during steady-state exercise of longer duration remains unknown. Lumbar intrathecal fentanyl was used to attenuate the central projection of group III/IV leg muscle afferents during prolonged locomotor exercise (i.e. 45 min) at intensities ranging from 50% to 100% of V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ . Without affecting the metabolic rate, afferent blockade compromised pulmonary ventilation and gas exchange efficiency, consistently impairing arterial oxygenation and facilitating respiratory acidosis throughout exercise. These findings reflect the time-independent significance of feedback from group III/IV muscle afferents for regulating exercise hyperpnoea and gas exchange efficiency, and thus for optimizing arterial oxygenation and acid-base balance, during prolonged human locomotion.

Incorporation of nitrogen in antinutritional Solanum alkaloid biosynthesis.

Steroidal glycoalkaloids (SGAs) are specialized metabolites produced by hundreds of Solanum species including food crops, such as tomato, potato and eggplant. Unlike true alkaloids, nitrogen is introduced at a late stage of SGA biosynthesis through an unknown transamination reaction. Here, we reveal the mechanism by which GLYCOALKALOID METABOLISM12 (GAME12) directs the biosynthesis of nitrogen-containing steroidal alkaloid aglycone in Solanum. We report that GAME12, a neofunctionalized γ-aminobutyric acid (GABA) transaminase, undergoes changes in both active site specificity and subcellular localization to switch from its renown and generic activity in core metabolism to function in a specialized metabolic pathway. Moreover, overexpression of GAME12 alone in engineered S. nigrum leaves is sufficient for de novo production of nitrogen-containing SGAs. Our results highlight how hijacking a core metabolism GABA shunt enzyme is crucial in numerous Solanum species for incorporating a nitrogen to a steroidal-specialized metabolite backbone and form defensive alkaloids.

Azithromycin Prevents Subglottic Stenosis in Mice.

OBJECTIVE: Pediatric subglottic stenosis (SGS) is characterized by subglottic narrowing which occurs when pathological fibroblasts deposit extracellular matrix that reduces airway patency. Recent clinical observations have suggested that azithromycin may have favorable impacts on SGS reduction while treating airway infections; furthermore, our recent work in mice demonstrated that the airway microbiome influences SGS. In this work, we characterize the protective effect of azithromycin as an immunomodulatory and antibacterial therapeutic against subglottic stenosis. METHODS: Immunomodulatory and antifibrotic effects of azithromycin were assessed on TGF-ß1-stimulated airway fibroblasts at 10 µg/mL for 5 days. Changes in gene expression were quantified by RT-qPCR and myofibroblast differentiation by α-SMA immunostaining. Murine airways were pretreated (2-weeks) with intranasal azithromycin before SGS injury by a twisted wire brush. Disease severity and immune response were characterized by histology and immunostaining for immune cells. RESULTS: In vitro, azithromycin treatment of TGF-ß1-stimulated fibroblasts exhibited strong reductions in extracellular matrix (COL1A1, LOX) and myofibroblast-related gene expression (ACTA2). Notably, there was a significant reduction in pro-fibrotic expression, which was observed with 10 µg/mL azithromycin. Immunostaining of fibroblasts for α-SMA revealed strong reductions in the number of positive-staining cells and the intensity of each positive cell. In vivo, azithromycin exhibited a significant decrease in lamina propria thickness indicative of reduced stenosis with associated changes in T-cell infiltration. CONCLUSIONS: Overall, we show azithromycin prevents pro-fibrotic gene expression and myofibroblast differentiation and can help protect mice from developing SGS. This introduces azithromycin as a potential treatment for SGS. LEVEL OF EVIDENCE: NA Laryngoscope, 2024.

Tranexamic Acid is Not Associated With a Change in Infection Risk in Trauma Patients.

INTRODUCTION: Tranexamic acid (TXA) has been used as an adjunct in traumatic hemorrhage management. Outside of trauma, TXA has been used to limit blood loss across multiple surgical fields. TXA has also been found to have an immune-modulating effect, reducing postoperative infection rates. However, the relationship between TXA and infection rates in trauma patients is unclear. METHODS: We performed a single-institution retrospective cohort analysis of 364 trauma patients who underwent massive transfusion protocol activation at a level-one trauma level center over a 7-y period. Patients were placed into two groups based on TXA administration (No TXA and TXA). Minors, patients on anticoagulants, pregnant patients, and those who died upon arrival or were hospitalized for less than 1 d were excluded. Univariate and multivariate analysis with propensity score matching were used to evaluate the association between TXA and infection rates. RESULTS: Sixty-one patients (16.8%) received TXA, and 303 patients (83.2%) did not. TXA was associated with an increased risk of infection on univariate analysis (P = 0.007). However, on multivariate analysis after propensity score matching, TXA was not associated with infection (P = 0.975) while total hospital days and total ventilator days were associated with an increased risk of infection (P = 0.012, P = 0.014). CONCLUSIONS: Our study found no association between TXA and infection rates among our patient cohort. While TXA remains an important adjunct in trauma resuscitation, we did not find an association between TXA and infection in trauma patients.

SQuID (subcutaneous insulin in diabetic ketoacidosis): Clinician acceptability.

BACKGROUND: We previously implemented the SQuID protocol (subcutaneous insulin in diabetic ketoacidosis [DKA]) demonstrating safe, effective treatment of low- to moderate-severity DKA in a non-intensive care unit setting. Since success and sustainability of interventions rely on staff buy-in, we assessed acceptability of SQuID among emergency department (ED) and inpatient clinicians. METHODS: We conducted a cross-sectional study in an urban academic hospital (March 2023-November 2023), surveying ED nurses (RNs) and physicians (MDs) and floor RNs and MDs treating patients on SQuID via emailed survey links. Clinicians could only take the survey once. We used Sekhon's Theoretical Framework of Acceptability, validated for staff acceptability of a new intervention, assessing eight domains with 5-point Likert responses. Clinicians were asked about prior experience with SQuID, and we assessed ED MD and RN preference (SQuID vs. intravenous [IV] insulin). Surveys included free-text boxes for comments. We present descriptive statistics including proportions with 95% confidence interval and medians with interquartile ranges (IQRs) and conducted thematic analysis of free-text comments. RESULTS: Our overall response rate (107/133) was 80% (34/42 ED RNs, 13/16 floor RNs, 47/57 ED MDs, 13/17 floor MDs), with first-time users of SQuID ranging from 7.7% (hospitalist MDs) to 35.3% (ED RNs) of participants. ED clinicians preferred SQuID over IV insulin (67% vs. 12%, 21% no preference). Acceptability was high across all domains and clinician types (median 4, IQR 4-5). Overall percentage of positive responses (4s and 5s) across domains was 92% (ED RNs [89%], floor RNs [89%], ED MDs [97%], floor MDs [87%]). We identified several themes among participant comments. CONCLUSIONS: Acceptability was high across clinician types; 65% of ED clinicians preferred SQuID to IV insulin. Clinicians liked SQuID (affective attitude), found it easy to use (burden), were confident in its use (self-efficacy), felt that it improved outcomes (perceived effectiveness), found that it was fair to patients (ethicality), found that it made sense (intervention coherence), and found that it did not interfere with other activities (opportunity cost).