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Advanced systemic mastocytosis (AdvSM) is a rare hematologic malignancy with organ damage and compromised life expectancy arising from organ accumulation of neoplastic mast cells. Identification of the gain-of-function KITD816V in the majority of cases has accelerated pharmaceutical development culminating with the development of selective KIT inhibitors such as avapritinib. While the advent of these therapies has improved the quality and quantity of life in patients with AdvSM, current challenges remain in the management of this disease. In this review, we summarize the present and future therapeutics landscape of AdvSM, highlighting the development of novel KIT inhibitors including elenestinib and bezuclastinib. We also explore the continued role of additional treatment modalities including allogeneic stem cell transplantation before discussing unresolved clinical challenges in the management of AdvSM.

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OBJECTIVE: To assess the desirability, feasibility, and sustainability of integrating a project-based capstone course with the course-based curriculum of an interdisciplinary MSc health informatics program guided with a student-partnered steering committee and student-centered approach. METHODS: We conducted an online cross-sectional survey (n=87) and three semi-structured focus groups (n=18) of health informatics students and alumni. Survey data was analyzed descriptively. Focus groups were audio-recorded and transcribed verbatim and then analyzed using a general inductive and classic analysis approach. RESULTS: Most students were supportive of including a capstone project but desired an option to work independently or within a group. Students perceived several benefits to capstone courses while concerned over perceived challenges to capstone implementation, evaluation, and managing group processes. Themes identified were: 1) professional development, identity, and career advancement; 2) emulating the real world and learning beyond the classroom, 3) embracing new, full circle learning, 4) anticipated course structure, delivery, and preparation, 5) balancing student choice, interests, and priorities, and 6) concerns over group dynamics, limitations, and support. CONCLUSIONS: This study demonstrates the value of having students as partners at each stage in the process from methods conception to course curriculum design. With the steering committee and the curriculum developer, we codeveloped a student-centered course that integrates foundational digital health-related project knowledge acquisition with an inquiry-based project which can be completed independently or in small groups. This study demonstrates the potential benefits and challenges that health informatics educators may consider when (re)-designing capstone courses.

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BACKGROUND: Asthma is a leading cause of children's hospitalizations, emergency department visits, and missed school days. Our school-based asthma intervention has reduced asthma exacerbations for children experiencing health disparities in the Denver Metropolitan Area, due partly to addressing care coordination for asthma and social determinants of health (SDOH), such as access to healthcare and medications. Limited dissemination of school-based asthma programs has occurred in other metropolitan and rural areas of Colorado. We formed and engaged community advisory boards in socioeconomically diverse regions of Colorado to develop two implementation strategy packages for delivering our school-based asthma intervention - now termed "Better Asthma Control for Kids (BACK)" - with tailoring to regional priorities, needs and resources. METHODS: In this proposed type 2 hybrid implementation-effectiveness trial, where the primary goal is equitable reach to families to reduce asthma disparities, we will compare two different packages of implementation strategies to deliver BACK across four Colorado regions. The two implementation packages to be compared are: 1) standard set of implementation strategies including Tailor and Adapt to context, Facilitation and Training termed, BACK-Standard (BACK-S); 2) BACK-S plus an enhanced implementation strategy, that incorporates network weaving with community partners and consumer engagement with school families, termed BACK-Enhanced (BACK-E). Our evaluation will be guided by the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework, including its Pragmatic Robust Implementation Sustainability Model (PRISM) determinants of implementation outcomes. Our central hypothesis is that our BACK-E implementation strategy will have significantly greater reach to eligible children/families than BACK-S (primary outcome) and that both BACK-E and BACK-S groups will have significantly reduced asthma exacerbation rates ("attacks") and improved asthma control as compared to usual care. DISCUSSION: We expect both the BACK-S and BACK-E strategy packages will accelerate dissemination of our BACK program across the state - the comparative impact of BACK-S vs. BACK-E on reach and other RE-AIM outcomes may inform strategy selection for scaling BACK and other effective school-based programs to address chronic illness disparities. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT06003569, registered on August 22, 2023, https://classic. CLINICALTRIALS: gov/ct2/show/NCT06003569 .

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Older/unfit adults with AML have worse outcomes and fewer treatment options than their younger/fit counterparts. In vitro studies have found a synergistic effect of hypomethylating agents (HMA) with venetoclax (VEN) on AML cells and since the phase 3 VIALE-A trial demonstrated a survival benefit, HMA + VEN has become the standard of care in the frontline setting for older/unfit adults with AML. Unfortunately, the standard 28-day cycle of VEN is associated with a high degree of myelosuppression leading to treatment delays and dose modifications. Many small retrospective studies have successfully shown comparable outcomes to VIALE-A with reduced dose/duration of VEN. Furthermore, low dose metronomic dosing of HMA + VEN has shown clinical benefit while minimizing myelotoxicity. Future trials are vital to understand the appropriate dose of VEN in combination with HMA, to evaluate HMA + VEN compared to intensive therapy for younger/fit patients, and to explore its utility in the relapsed/refractory setting.

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In the published publication [...].

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Specific amino acid footprinting mass spectrometry (MS) is an increasingly utilized method for elucidating protein higher order structure (HOS). It does this by adding to certain amino acid residues a mass tag, whose reaction extent depends on solvent accessibility and microenvironment of the protein. Unlike reactive free radicals and carbenes, these specific footprinters react slower than protein unfolding. Thus, their footprinting, under certain conditions, provokes structural changes to the protein, leading to labeling on non-native structures. It is critical to establish conditions (i.e., reagent concentrations, time of reaction) to ensure that the structure of the protein following footprinting remains native. Here, we compare the efficacy of five methods in assessing protein HOS following footprinting at the intact protein level and then further localize the perturbation at the peptide level. Three are MS-based methods that provide dose-response plot analysis, evaluation of Poisson distributions of precursor and products, and determination of the average number of modifications. These MS-based methods reliably and effectively indicate HOS perturbation at the intact protein level, whereas spectroscopic methods (circular dichroism (CD) and dynamic light scattering (DLS)) are less sensitive in monitoring subtle HOS perturbation caused by footprinting. Evaluation of HOS at the peptide level indicates regions that are sensitive to localized perturbations. Peptide-level analysis also provides higher resolution of the HOS perturbation, and we recommend using it for future footprinting studies. Overall, this work shows conclusive evidence for HOS perturbation caused by footprinting. Implementation of quality control workflows can identify conditions to avoid the perturbation, for footprinting, allowing accurate and reliable identification of protein structural changes that accompany, for example, ligand interactions, mutations, and changes in solution environment.

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Microglia help limit the progression of Alzheimer's disease (AD) by constraining amyloid-ß (Aß) pathology, effected through a balance of activating and inhibitory intracellular signals delivered by distinct cell surface receptors. Human leukocyte Ig-like receptor B4 (LILRB4) is an inhibitory receptor of the immunoglobulin (Ig) superfamily that is expressed on myeloid cells and recognizes apolipoprotein E (ApoE) among other ligands. Here, we find that LILRB4 is highly expressed in the microglia of patients with AD. Using mice that accumulate Aß and carry a transgene encompassing a portion of the LILR region that includes LILRB4, we corroborated abundant LILRB4 expression in microglia wrapping around Aß plaques. Systemic treatment of these mice with an anti-human LILRB4 monoclonal antibody (mAb) reduced Aß load, mitigated some Aß-related behavioral abnormalities, enhanced microglia activity, and attenuated expression of interferon-induced genes. In vitro binding experiments established that human LILRB4 binds both human and mouse ApoE and that anti-human LILRB4 mAb blocks such interaction. In silico modeling, biochemical, and mutagenesis analyses identified a loop between the two extracellular Ig domains of LILRB4 required for interaction with mouse ApoE and further indicated that anti-LILRB4 mAb may block LILRB4-mApoE by directly binding this loop. Thus, targeting LILRB4 may be a potential therapeutic avenue for AD.

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Polycythemia vera is a Philadelphia chromosome-negative myeloproliferative neoplasm characterized by the clonal proliferation of hematopoietic cells, leading to the overproduction of erythrocytes and the elaboration of inflammatory cytokines. Management is aimed at reducing the risk of thromboembolic events, alleviating the symptom burden, decreasing splenomegaly, and potentially mitigating the risk of disease progression. Existing treatment options include therapeutic phlebotomy and cytoreductive agents including hydroxyurea, pegylated recombinant interferon alpha 2a, ropegylated recombinant interferon alpha 2b, and ruxolitinib. We review risk factors for both thrombotic events and disease progression in patients with polycythemia vera. We discuss existing and novel therapeutic approaches to mitigate the risk of disease-related complications and progression.

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Targeted delivery and cell-type-specific expression of gene-editing proteins in various cell types in vivo represent major challenges for all viral and non-viral delivery platforms developed to date. Here, we describe the development and analysis of artificial vectors for intravascular delivery (AVIDs), an engineered adenovirus-based gene delivery platform that allows for highly targeted, safe, and efficient gene delivery to human hematopoietic stem and progenitor cells (HSPCs) in vivo after intravenous vector administration. Due to a set of refined structural modifications, intravenous administration of AVIDs did not trigger cytokine storm, hepatotoxicity, or thrombocytopenia. Single intravenous administration of AVIDs to humanized mice, grafted with human CD34+ cells, led to up to 20% transduction of CD34+CD38-CD45RA- HSPC subsets in the bone marrow. Importantly, targeted in vivo transduction of CD34+CD38-CD45RA-CD90-CD49f+ subsets, highly enriched for human hematopoietic stem cells (HSCs), reached up to 19%, which represented a 1,900-fold selectivity in gene delivery to HSC-enriched over lineage-committed CD34-negative cell populations. Because the AVID platform allows for regulated, cell-type-specific expression of gene-editing technologies as well as expression of immunomodulatory proteins to ensure persistence of corrected HSCs in vivo, the HSC-targeted AVID platform may enable development of curative therapies through in vivo gene correction in human HSCs after a single intravenous administration.

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BACKGROUND: Dilated cardiomyopathy with ataxia (DCMA) is an autosomal recessive disorder arising from truncating mutations in DNAJC19, which encodes an inner mitochondrial membrane protein. Clinical features include an early onset, often life-threatening, cardiomyopathy associated with other metabolic features. Here, we aim to understand the metabolic and pathophysiological mechanisms of mutant DNAJC19 for the development of cardiomyopathy. METHODS: We generated induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) of two affected siblings with DCMA and a gene-edited truncation variant (tv) of DNAJC19 which all lack the conserved DnaJ interaction domain. The mutant iPSC-CMs and their respective control cells were subjected to various analyses, including assessments of morphology, metabolic function, and physiological consequences such as Ca2+ kinetics, contractility, and arrhythmic potential. Validation of respiration analysis was done in a gene-edited HeLa cell line (DNAJC19tvHeLa). RESULTS: Structural analyses revealed mitochondrial fragmentation and abnormal cristae formation associated with an overall reduced mitochondrial protein expression in mutant iPSC-CMs. Morphological alterations were associated with higher oxygen consumption rates (OCRs) in all three mutant iPSC-CMs, indicating higher electron transport chain activity to meet cellular ATP demands. Additionally, increased extracellular acidification rates suggested an increase in overall metabolic flux, while radioactive tracer uptake studies revealed decreased fatty acid uptake and utilization of glucose. Mutant iPSC-CMs also showed increased reactive oxygen species (ROS) and an elevated mitochondrial membrane potential. Increased mitochondrial respiration with pyruvate and malate as substrates was observed in mutant DNAJC19tv HeLa cells in addition to an upregulation of respiratory chain complexes, while cellular ATP-levels remain the same. Moreover, mitochondrial alterations were associated with increased beating frequencies, elevated diastolic Ca2+ concentrations, reduced sarcomere shortening and an increased beat-to-beat rate variability in mutant cell lines in response to ß-adrenergic stimulation. CONCLUSIONS: Loss of the DnaJ domain disturbs cardiac mitochondrial structure with abnormal cristae formation and leads to mitochondrial dysfunction, suggesting that DNAJC19 plays an essential role in mitochondrial morphogenesis and biogenesis. Moreover, increased mitochondrial respiration, altered substrate utilization, increased ROS production and abnormal Ca2+ kinetics provide insights into the pathogenesis of DCMA-related cardiomyopathy.

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Viral inclusion bodies (IBs) are potential sites of viral replication and assembly. How viral IBs form remains poorly defined. Here we describe a combined biophysical and cellular approach to identify the components necessary for IB formation during Ebola virus (EBOV) infection. We find that the eNP0VP35 complex containing Ebola nucleoprotein (eNP) and viral protein 35 (eVP35), the functional equivalents of nucleoprotein (N) and phosphoprotein (P) in non-segmented negative strand viruses (NNSVs), phase separates to form inclusion bodies. Phase separation of eNP0VP35 is reversible and modulated by ionic strength. The multivalency of eVP35, and not eNP, is also critical for phase separation. Furthermore, overexpression of an eVP35 peptide disrupts eNP0VP35 complex formation, leading to reduced frequency of IB formation and limited viral infection. Together, our results show that upon EBOV infection, the eNP0VP35 complex forms the minimum unit to drive IB formation and viral replication.

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Recent dissection studies resulted in the introduction of the term "chiasma antebrachii", which represents an intersection of the flexor digitorum superficialis (FDS) tendons for digits 2 and 3 in the distal third of the forearm. This retrospective investigation aimed to provide an MRI-based morphologic analysis of the chiasma antebrachii. In 89 patients (41 women, 39.3 ± 21.3 years), MRI examinations of the forearm (2010-2021) were reviewed by two radiologists, who evaluated all studies for the presence and length of the chiasma as well as its distance from the distal radioulnar and elbow joint. The chiasma antebrachii was identified in the distal third of the forearm in 88 patients (98.9%), while one intersection was located more proximally in the middle part. The chiasma had a median length of 28 mm (interquartile range: 24-35 mm). Its distances to the distal radioulnar and elbow joint were 16 mm (8-25 mm) and 215 mm (187-227 mm), respectively. T1-weighted post-contrast sequences were found to be superior to T2- or proton-density-weighted sequences in 71 cases (79.8%). To conclude, the chiasma antebrachii is part of the standard FDS anatomy. Knowledge of its morphology is important, e.g., in targeted injections of therapeutics or reconstructive surgery.

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Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that play important roles in cell proliferation, differentiation, metabolism, and cancer [...].

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Adenovirus has strong therapeutic potential as an oncolytic virus and gene therapy vector. However, injecting human species C serotype 5 adenovirus, HAdv-C5, into the bloodstream leads to numerous interactions with plasma proteins that affect viral tropism and biodistribution, and can lead to potent immune responses and viral neutralization. The HAdv/factor X (FX) interaction facilitates highly efficient liver transduction and protects virus particles from complement-mediated neutralization after intravenous delivery. Ablating the FX interaction site on the HAdv-C5 capsid leaves the virus susceptible to neutralization by natural IgM followed by activation of the complement cascade and covalent binding of complement components C4b and C3b to the viral capsid. Here we present structural models for IgM and complement components C1, C4b, and C3b in complex with HAdv-C5. Molecular dynamics simulations indicate that when C3b binds near the vertex, multiple stabilizing interactions can be formed between C3b, penton base, and fiber. These interactions may stabilize the vertex region of the capsid and prevent release of the virally encoded membrane lytic factor, protein VI, which is packaged inside of the viral capsid, thus effectively neutralizing the virus. In a situation where FX and IgM are competing for binding to the capsid, IgM may not be able to form a bent conformation in which most of its Fab arms interact with the capsid. Our structural modeling of the competitive interaction of FX and IgM with HAdv-C5 allows us to propose a mechanistic model for FX inhibition of IgM-mediated virus neutralization. According to this model, although IgM may bind to the capsid, in the presence of FX it will likely retain a planar conformation and thus be unable to promote activation of the complement cascade at the virus surface.

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Protein footprinting mass spectrometry probes protein higher order structure and dynamics by labeling amino acid side-chains or backbone amides as a function of solvent accessibility. One category of footprinting uses residue-specific, irreversible covalent modifications, affording flexibility of sample processing for bottom-up analysis. Although several specific amino acid footprinting technologies are becoming established in structural proteomics, there remains a need to assess fundamental properties of new reagents before their application. Often, footprinting reagents are applied to complex or novel protein systems soon after their discovery and sometimes without a thorough investigation of potential downsides of the reagent. In this work, we assemble and test a validation workflow that utilizes cyclic peptides and a model protein to characterize benzoyl fluoride, a recently published, next-generation nucleophile footprinter. The workflow includes the characterization of potential side-chain reactive groups, reaction "quench" efficacies, reagent considerations and caveats (e.g., buffer pH), residue-specific kinetics compared to those of established reagents, and protein-wide characterization of modification sites with considerations for proteolysis. The proposed workflow serves as a starting point for improved footprinting reagent discovery, validation, and introduction, the aspects of which we recommend before applying to unknown protein systems.

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Lone star ticks (Amblyomma americanum L.) are expanding within the northeast United States, a region historically focused on Ixodes scapularis-transmitted diseases. In Monmouth County, NJ, the shift has been dramatic, and lone star ticks now vastly outnumber blacklegged ticks. As a result, there is an enhanced need to focus on the potential health risks of A. americanum-transmitted pathogens, such as the emerging Heartland (HRTV) and Bourbon (BRBV) viruses. We screened 1,205 nymphal lone star ticks for HRTV and BRBV using RT-qPCR assays and detected BRBV in 3 ticks collected in Monmouth County, NJ, in 2021. Additionally, we sequenced a complete BRBV genome from a single infected specimen, finding 99.4% identity with human pathogenic isolates from the eastern-central United States. Our results have important public health implications for a region only recently becoming aware of public health risks posed by lone star ticks. Of note, we report successful detection of viral RNA in samples that were stored and intended for DNA preservation, for example, kept in ethanol at room temperature, which may reduce barriers for public health agencies seeking to expand their tick testing to include viruses.

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During development, the heart is the first organ to form and function [...].

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The Wilms tumor suppressor gene (Wt1) encodes a C2H2-type zinc-finger transcription factor that participates in transcriptional regulation, RNA metabolism, and protein-protein interactions. WT1 is involved in the development of several organs, including the kidneys and gonads, heart, spleen, adrenal glands, liver, diaphragm, and neuronal system. We previously provided evidence of transient WT1 expression in about 25% of cardiomyocytes of mouse embryos. Conditional deletion of Wt1 in the cardiac troponin T lineage caused abnormal cardiac development. A low expression of WT1 has also been reported in adult cardiomyocytes. Therefore, we aimed to explore its function in cardiac homeostasis and in the response to pharmacologically induced damage. Silencing of Wt1 in cultured neonatal murine cardiomyocytes provoked alterations in mitochondrial membrane potential and changes in the expression of genes related to calcium homeostasis. Ablation of WT1 in adult cardiomyocytes by crossing αMHCMerCreMer mice with homozygous WT1-floxed mice induced hypertrophy, interstitial fibrosis, altered metabolism, and mitochondrial dysfunction. In addition, conditional deletion of WT1 in adult cardiomyocytes increased doxorubicin-induced damage. These findings suggest a novel role of WT1 in myocardial physiology and protection against damage.