Faculty Bibliography

Each olfactory cortical hemisphere receives ipsilateral odor information directly from the olfactory bulb and contralateral information indirectly from the other cortical hemisphere. Since neural projections to the olfactory cortex (OC) are disordered and nontopographic, spatial information cannot be used to align projections from the two sides like in the visual cortex. Therefore, how bilateral information is integrated in individual cortical neurons is unknown. We have found, in mice, that the odor responses of individual neurons to selective stimulation of each of the two nostrils are significantly correlated, such that odor identity decoding optimized with information arriving from one nostril transfers very well to the other side. Nevertheless, these aligned responses are asymmetric enough to allow decoding of stimulus laterality. Computational analysis shows that such matched odor tuning is incompatible with purely random connections but is explained readily by Hebbian plasticity structuring bilateral connectivity. Our data reveal that despite the distributed and fragmented sensory representation in the OC, odor information across the two hemispheres is highly coordinated.

Nerve growth factor (NGF) monoclonal antibodies inhibit chronic pain, yet failed to gain approval due to worsened joint damage in osteoarthritis patients. We report that neuropilin-1 (NRP1) is a coreceptor for NGF and tropomyosin-related kinase A (TrkA) pain signaling. NRP1 was coexpressed with TrkA in human and mouse nociceptors. NRP1 inhibitors suppressed NGF-stimulated excitation of human and mouse nociceptors and NGF-evoked nociception in mice. NRP1 knockdown inhibited NGF/TrkA signaling, whereas NRP1 overexpression enhanced signaling. NGF bound NRP1 with high affinity and interacted with and chaperoned TrkA from the biosynthetic pathway to the plasma membrane and endosomes, enhancing TrkA signaling. Molecular modeling suggested that the C-terminal R/KXXR/K NGF motif interacts with the extracellular "b" NRP1 domain within a plasma membrane NGF/TrkA/NRP1 of 2:2:2 stoichiometry. G α interacting protein C-terminus 1 (GIPC1), which scaffolds NRP1 and TrkA to myosin VI, colocalized in nociceptors with NRP1/TrkA. GIPC1 knockdown abrogated NGF-evoked excitation of nociceptors and pain-like behavior. Thus, NRP1 is a nociceptor-enriched coreceptor that facilitates NGF/TrkA pain signaling. NRP binds NGF and chaperones TrkA to the plasma membrane and signaling endosomes via the GIPC1 adaptor. NRP1 and GIPC1 antagonism in nociceptors offers a long-awaited nonopioid alternative to systemic antibody NGF sequestration for the treatment of chronic pain.

BACKGROUND/UNASSIGNED:I-PU-H71 is an imaging biomarker of epichaperome formation. The tracer has been established to localize in tissues under chronic stress, specifically in cancer cells and neurodegenerative brain cells. A first-in-human imaging trial using positron emission tomography (PET) in cancer patients revealed unexpected tracer accumulation in the myocardium. PURPOSE/UNASSIGNED:I-PU-H71 myocardial biodistribution and pharmacokinetics in a series of cancer patients with no history of cardiovascular disease. METHODS/UNASSIGNED:I-PU-H71 while at rest, followed by dynamic and gated/non-gated PET image data acquisitions. Region-of-interest (ROI) analysis of left ventricular myocardium (LVmyo) and background left atrium quantified tracer concentrations as standardized uptake value (SUV) and uptake ratios. Kinetic rate constants were evaluated by a two-tissue compartment model. RESULTS/UNASSIGNED:(IQR, 0.0015-0.0057). Regional assessment demonstrated essentially uniform tracer uptake in LV and myocardial segments; with normal LVEF in all patients (mean 57.7 ± 3.5%); and no patients suffered cardiac events over subsequent 12-month period. CONCLUSION/UNASSIGNED:I-PU-H71 PET. Our data indicates PU-H71 PET merits further study as a myocardial epichaperome biomarker, with potential application in drug development, possibly as a biomarker in subclinical cardiac dysfunction.

AIMS/UNASSIGNED:) to impute missing alcohol data in a prospective study among pregnant women. METHODS/UNASSIGNED:imputed values were weighted for the distances and matched for the day of the week. Since participants with no missing days were not comparable to those with missing data, segments of non-missing data from all participants were included as a reference. Validation was done after randomly deleting data for 5-15 consecutive days from the first trimester. RESULTS/UNASSIGNED:We found that data from 5 nearest neighbors (i.e., K = 5) and segments of 55 days provided imputed values with least imputation error. After deleting data segments from the first trimester data set with no missing days, there was no difference between actual and predicted values for 64% of deleted segments. For 31% of the segments, imputed data were within +/-1 drink/day of the actual. Imputation accuracy varied by study site because of the differences in the magnitude of drinking and proportion of missing data. CONCLUSION/UNASSIGNED:

Psychological safety is the belief that one will not be punished or humiliated for speaking up, sharing ideas, raising concerns, or making mistakes. There are various threats to psychological safety in health professions education (HPE). This commentary applies Clark's model of psychological safety (Inclusion Safety, Learner Safety, Contributor Safety, Challenger Safety) to five different HPE settings (classroom instructions, clinical training, simulation-based training, online instructions, interprofessional education). Setting-specific threats and strategies for enhancing psychological safety are discussed.

BACKGROUND:Data on procedural and early outcomes after transjugular transcatheter tricuspid valve replacement (TTVR) are limited. OBJECTIVES/OBJECTIVE:This study sought to evaluate first-in-man procedural and clinical outcomes after transjugular TTVR with a special focus on patients who received large device sizes in whom TTVR outcomes have been questioned. METHODS:The retrospective registry included patients who underwent TTVR using the LuX-Valve Plus system (Jenscare Biotechnology Co Ltd) for symptomatic tricuspid regurgitation (TR) from January 2022 until February 2024 at 15 international centers in a compassionate use setting. The endpoints were procedural TR reduction, in-hospital death, adverse events, and 1-month survival. We further stratified results according to the size of the implanted device (<55 vs ≥55 mm). RESULTS:The registry included a total of 76 patients at a median age of 78 years (Q1-Q3: 72-83 years, 47.4% women). TR was reduced to ≤2+ and ≤1+ in 94.7% and 90.8% of patients (75.0% of patients received TTVR devices ≥55 mm) with well-sustained results at 1-month follow-up (TR ≤2+ in 95.0% and ≤1+ 86.8%). Residual TR was paravalvular in all cases. In-hospital death occurred in 4 patients (5.3%). Four patients (5.3%) underwent cardiac surgery during index hospitalization. Major in-hospital bleeding events occurred in 5 patients (6.6%). New in-hospital pacemaker implantation was required in 3.9% of patients in the overall cohort (5.7% in "pacemaker-naive" individuals). No cases of valve thrombosis, stroke, myocardial infarction, or pulmonary embolism were observed. At 1-month follow-up, survival was 94.4%, and NYHA functional class significantly improved. One further patient received a pacemaker, 1 further bleeding event occurred, and 2 patients underwent reintervention or surgery within the first 30 days after TTVR. No differences in procedural outcomes or adverse events were observed after stratification for valve size. CONCLUSIONS:Transjugular TTVR appears to be a safe and effective treatment option for patients with severe TR with comparable outcomes in very large tricuspid anatomies.

With the recent approval of the transcatheter EVOQUE tricuspid valve replacement system to treat severe, symptomatic tricuspid regurgitation, there is a need to define the appropriate patient population and anatomical considerations for this device. In this consensus document, the authors review these considerations, describe the procedural steps and imaging requirements to ensure technical success, and discuss management of complex intraprocedural circumstances.

BACKGROUND:Calcific mitral stenosis (calcific MS) presents a challenge for surgical treatment and is a contraindication for most contemporary transcatheter mitral valve replacement devices (TMVR), rendering patients with very limited therapeutic options. AIMS/OBJECTIVE:This study aims to assess the clinical and hemodynamic follow-up after mitral valve lithotripsy (MVL). METHODS:All consecutive patients who underwent MVL to treat symptomatic calcific MS at St Michael's Hospital, Toronto, Canada, were included. Patients were deemed unsuitable for mitral surgery or TMVR after heart team assessment. Patients with rheumatic MS or ≥moderate mitral regurgitation (MR) were excluded. The primary endpoint was a reduction in the invasive mitral gradient by ≥50% without significant (≥moderate) MR. RESULTS:Fifteen patients underwent MVL between 2021 and 2023 with a mean age of 74 ± 9 years; 53% were female, with a mean STS score of 10% ± 0.1%. Following MVL, there was a reduction in the invasively measured mean trans-mitral gradient compared to baseline (14 mmHg vs. 6 mmHg; p < 0.05). The primary endpoint was achieved in 8 patients (53%) with no major procedural complications. At follow-up (median 90 days, IQR 58-115 days), 14 (93%) patients reported improved symptoms from New York Heart Association (NYHA) Class III-IV to NYHA Class I-II (p < 0.01) with stable echo-derived mean gradient (7.7 mmHg ± 2 mmHg vs. 8.4 mmHg ± 2.9 mmHg (p = 0.7). CONCLUSIONS:In selected patients with symptomatic inoperable calcific MS, MVL was safe and associated with significant short-term clinical and hemodynamic improvement. MVL may represent a new compassionate therapy for this challenging cohort. Further studies are needed to determine the long-term outcomes and help define the role of IVL technology in treating calcific valvular conditions.