Citations

ABSTRACT Research is important to advance the field of emergency medicine and improve patient care. As such, emergency medicine residents are required to complete a scholarly project during their training. This experience provides an opportunity to enhance their exposure to research, expanding their skillset as both producers and consumers of the medical literature. However, the process may be overwhelming to launch, especially for residents. This Educator's Blueprint will provide 10 strategies for navigating and optimizing the resident research experience. These strategies include providing structured training, creating a research‐supportive environment, selecting a project using resident‐centric FINER criteria, identifying a research mentor, creating mosaic research experiences, setting expectations, empowering residents, selecting team members for sustainability, providing scaffolding and support during the writing stage, and explaining the peer review process and normalizing rejection or revisions. These strategies will help guide faculty seeking to enhance their learners' research experience.

Abstract A low-cost, easy-to-adopt noninvasive imaging modality for differentiating bacterial infection from inflammation is desirable to accurately diagnose bacterial infections. Herein, a bacteria-specific PET probe, [68Ga]Ga-BP, was developed and evaluated in rat models of foreign body-associated osteomyelitis induced by methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae and was directly compared with sterile inflammation and uninstrumented uninfected controls. [68Ga]Ga-BP-based imaging of MRSA-infected tibiae was also compared to [68Ga]Ga-citrate and [18F]FDG. After iron depletion, dynamic PET/CT imaging was performed at 15–120 min postinjection of radiotracers, followed by assessment of ex vivo biodistribution. [68Ga]Ga-BP successfully detected tibial infection and demonstrated >6-fold higher uptake in infected tibiae with all three bacterial species versus contralateral tibiae via PET imaging. [68Ga]Ga-BP outperformed [68Ga]Ga-citrate and [18F]FDG in identifying MRSA infection. [68Ga]Ga-BP represents a promising, noninvasive PET imaging agent for direct bacterial detection and bacterial infection treatment monitoring.

Objective Long COVID (LC) refers to the long-term symptoms occurring after SARS-CoV-2 infection and resolution of the initial disease prodrome. While LC is increasingly recognized, knowledge about its biomarkers is still limited. This study examines imaging findings in 18 F-FDG PET-CT scans in 40 patients with LC from an academic LC Clinic, for potential imaging biomarkers. Methods This study included patients aged 18 and older with confirmed positive SARS-CoV-2 PCR test and at least 28 days post-symptom onset. 18 F-FDG PET-CT scans were performed, and brain metabolic activity was compared to a control database to generate Z-scores. Participants were grouped based on their clinical phenotype and Z-scores of different brain regions were analyzed using t-tests. Results The study group was mainly female (70%), with a median age of 53 years, and predominantly non-Hispanic White (90%). Most had pre-existing conditions such as gastrointestinal, cardiovascular, endocrine, and psychiatric disorders. The findings showed significant cerebral hypometabolism in 29 patients with fatigue and post-exertional malaise (PEM), particularly in the left sensorimotor cortex (p=0.0253) and bilateral primary visual cortex (right: p=0.0096, left: p=0.0016), which persisted up to two years after infection. Conclusions In summary, this study identified persistent cerebral hypometabolism in LC patients, especially those with fatigue with PEM, up to two years post-infection. These results suggest that 18 F-FDG PET-CT could be a valuable tool for diagnosing and managing LC. Further research is essential to confirm these findings and improve treatment strategies for patients with LC.

ABSTRACT The enteric nervous system (ENS) is a complex peripheral neural network that coordinates gastrointestinal motility through highly organized synaptic communication. Although tissue-resident muscularis macrophages (MMs) closely associate with enteric neurons, whether they regulate enteric synaptic organization remains unknown. In the central nervous system (CNS), microglia sculpt neural circuits through complement-dependent synaptic remodeling, raising the possibility that analogous neuroimmune mechanisms operate in the gut. Here, we identify a previously unrecognized role for C1qa□ MMs in regulating enteric synaptic homeostasis and gastrointestinal motility. Using macrophage-specific constitutive and inducible C1qa deletion models, single-cell RNA sequencing, enteric synaptosome proteomics, physiology, and advanced imaging, we demonstrate that loss of MMs-derived C1qa increases enteric synaptic density without altering neuronal numbers. C1qa deficiency induced broad transcriptional changes in enteric neurons and macrophages, including altered synapse-associated, lysosomal, and endocytic programs. Proteomic analysis revealed that enteric synapses share a conserved molecular architecture with brain synapses while exhibiting distinct gastrointestinal-specific complement-associated synaptic networks enriched for structural and receptor-localization pathways. Functionally, macrophage-specific C1qa deletion altered excitatory and inhibitory enteric neurotransmission, enhanced cholinergic signaling, reduced nitrergic responses, and accelerated gastrointestinal transit, while smooth muscle responsiveness remained preserved. C1qa□ MMs displayed transcriptional and functional features consistent with a phagocytic synapse-remodeling phenotype, including enrichment of complement, lysosomal, and engulfment pathways. Loss of C1qa impaired macrophage phagocytic activity both in vitro and in vivo and was associated with synapse accumulation and altered macrophage morphology. Importantly, inducible deletion of C1qa in adulthood recapitulated the synaptic and motility phenotypes, demonstrating that C1qa□ MMs continuously regulate enteric synaptic organization beyond development. Together, these findings identify a complement-dependent neuroimmune mechanism that regulates enteric circuit organization and gut motility, establishing MMs as active modulators of adult ENS synaptic homeostasis. Abstract Figure

Neuroplastic changes in phrenic motor neurons that underlie recovery from spinal cord injury may be mediated by perineuronal nets. We show that changes in perineuronal nets around phrenic motor neurons occur within 7 days after cervical spinal cord injury, and that the increase in perineuronal nets around larger phrenic motor neurons was more pronounced. These changes are consistent with substantial reorganization of the neural network onto intact phrenic motor neurons following cervical spinal cord injury.