Learning enhances behaviorally relevant representations in apical dendrites.

Learning alters cortical representations and improves perception. Apical tuft dendrites in cortical layer 1, which are unique in their connectivity and biophysical properties, may be a key site of learning-induced plasticity. We used both two-photon and SCAPE microscopy to longitudinally track tuft-wide calcium spikes in apical dendrites of layer 5 pyramidal neurons in barrel cortex as mice learned a tactile behavior.

Days-old zebrafish rapidly learn to recognize threatening agents through noradrenergic and forebrain circuits.

Animals need to rapidly learn to recognize and avoid predators. This ability may be especially important for young animals due to their increased vulnerability. It is unknown whether, and how, nascent vertebrates are capable of such rapid learning.

Mesoscale Brain Mapping: Bridging Scales and Modalities in Neuroimaging - A Symposium Review.

Advances in the spatiotemporal resolution and field-of-view of neuroimaging tools are driving mesoscale studies for translational neuroscience. On October 10, 2023, the Center for Mesoscale Mapping (CMM) at the Massachusetts General Hospital (MGH) Athinoula A. Martinos Center for Biomedical Imaging and the Massachusetts Institute of Technology (MIT) Health Sciences Technology based Neuroimaging Training Program (NTP) hosted a symposium exploring the state-of-the-art in this rapidly growing area of research.

Spectral-switching analysis reveals real-time neuronal network representations of concurrent spontaneous naturalistic behaviors in human brain.

Despite abundant evidence of functional networks in the human brain, their neuronal underpinnings, and relationships to real-time behavior have been challenging to resolve. Analyzing brain-wide intracranial-EEG recordings with video monitoring, acquired in awake subjects during clinical epilepsy evaluation, we discovered the tendency of each brain region to switch back and forth between 2 distinct power spectral densities (PSDs 2-55Hz). We further recognized that this 'spectral switching' occurs synchronously between distant sites, even between regions with differing baseline PSDs, revealing long-range functional networks that would be obscured in analysis of individual frequency bands.

Combined ion beam irradiation platform and 3D fluorescence microscope for cellular cancer research.

To improve particle radiotherapy, we need a better understanding of the biology of radiation effects, particularly in heavy ion radiation therapy, where global responses are observed despite energy deposition in only a subset of cells. Here, we integrated a high-speed swept confocally-aligned planar excitation (SCAPE) microscope into a focused ion beam irradiation platform to allow real-time 3D structural and functional imaging of living biological samples during and after irradiation. We demonstrate dynamic imaging of the acute effects of irradiation on 3D cultures of U87 human glioblastoma cells, revealing characteristic changes in cellular movement and intracellular calcium signaling following ionizing irradiation.

Why workshops work: Examining the efficacy of training trainers to train goats.

Experimental procedures involving farm animals are often associated with stress due to restraining. Stress can be reduced through use of positive reinforcement training, which then serves as refinement according to the 3Rs principles. Trainer skills, however, may influence the feasibility and success of animal training.

Development of entrustable professional activities for emergency medicine medical education fellowships: A modified Delphi study.

Background: It is essential that medical education (MedEd) fellows achieve desired outcomes prior to graduation. Despite the increase in postgraduate MedEd fellowships in emergency medicine (EM), there is no consistently applied competency framework. We sought to develop entrustable professional activities (EPAs) for EM MedEd fellows.

Comparison of the perioperative outcomes of using the Firefly system with indocyanine green during robotic-assisted cystectomy with urinary diversion.

Introduction: Use of indocyanine green (ICG) with near-infrared fluorescence (NIRF) has been demonstrated to be an effective tool for intraoperative assessment of bowel and ureteric vascularity. This study aimed to evaluate the impact of ICG on postsurgical outcomes such as anastomotic bowel leak and uretero-enteric stricture formation during robot-assisted cystectomy (RAC) and intracorporeal urinary diversion (ICUD).

Methods: We identified 238 patients who underwent RAC at the University of Louisville between September 2012 and August 2021.

Audiovisualization of real-time neuroimaging data.

Advancements in brain imaging techniques have significantly expanded the size and complexity of real-time neuroimaging and behavioral data. However, identifying patterns, trends and synchronies within these datasets presents a significant computational challenge. Here, we demonstrate an approach that can translate time-varying neuroimaging data into unique audiovisualizations consisting of audible representations of dynamic data merged with simplified, color-coded movies of spatial components and behavioral recordings.

Glioma-Induced Alterations in Excitatory Neurons are Reversed by mTOR Inhibition.

Gliomas are highly aggressive brain tumors characterized by poor prognosis and composed of diffusely infiltrating tumor cells that intermingle with non-neoplastic cells in the tumor microenvironment, including neurons. Neurons are increasingly appreciated as important reactive components of the glioma microenvironment, due to their role in causing hallmark glioma symptoms, such as cognitive deficits and seizures, as well as their potential ability to drive glioma progression. Separately, mTOR signaling has been shown to have pleiotropic effects in the brain tumor microenvironment, including regulation of neuronal hyperexcitability.

Genitourinary Blastomycosis in a Young Male Patient: A Case Report and Review of Diagnostic Challenges.

Disseminated blastomycosis is an endemic fungal infection that rarely manifests with genitourinary involvement. We present a unique case of a 28-year-old professional male gamer with a remote history of hemoptysis and cervical lymphadenopathy who presented with hematospermia, lower urinary tract symptoms (LUTS), and persistent groin abscesses after left orchiectomy at an outside hospital. He underwent drainage of groin abscess and prostate biopsy for an abnormal digital rectal exam which revealed disseminated blastomycosis requiring systemic, long-term antifungal treatment.

Neuromuscular basis of larval rolling escape behavior.

When threatened by dangerous or harmful stimuli, animals engage in diverse forms of rapid escape behaviors. In larvae, one type of escape response involves C-shaped bending and lateral rolling followed by rapid forward crawling. The sensory circuitry that promotes larval escape has been extensively characterized; however, the motor programs underlying rolling are unknown.

Colo-renal Fistula in a Patient With Refractory Anemia and Recurrent Urinary Tract Infections: A Case Report and Review of the Literature.

Although rare, colo-renal fistulas pose diagnostic challenges due to their varied presentations and etiologies. Here, we present a unique case of a woman with recurrent pyelonephritis, severe anemia, and unintended weight loss, who was eventually diagnosed with a colo-renal fistula. Delayed imaging following intraoperative fluoroscopy revealed the abnormal connection between the colon and upper urinary tract.

The mesencephalic locomotor region recruits V2a reticulospinal neurons to drive forward locomotion in larval zebrafish.

The mesencephalic locomotor region (MLR) is a brain stem area whose stimulation triggers graded forward locomotion. How MLR neurons recruit downstream vsx2 (V2a) reticulospinal neurons (RSNs) is poorly understood. Here, to overcome this challenge, we uncovered the locus of MLR in transparent larval zebrafish and show that the MLR locus is distinct from the nucleus of the medial longitudinal fasciculus.

Ex situ perfusion fixation for brain banking: a technical report.

Perfusion fixation is a well-established technique in animal research to improve preservation quality in the study of many tissues, including the brain. There is a growing interest in using perfusion to fix postmortem human brain tissue to achieve the highest fidelity preservation for downstream high-resolution morphomolecular brain mapping studies. Numerous practical barriers arise when applying perfusion fixation in brain banking settings, including the large mass of the organ, degradation of vascular integrity and patency prior to the start of the procedure, and differing investigator goals sometimes necessitating part of the brain to be frozen.

Cortex-wide neural dynamics predict behavioral states and provide a neural basis for resting-state dynamic functional connectivity.

Although resting-state functional magnetic resonance imaging (fMRI) studies have observed dynamically changing brain-wide networks of correlated activity, fMRI's dependence on hemodynamic signals makes results challenging to interpret. Meanwhile, emerging techniques for real-time recording of large populations of neurons have revealed compelling fluctuations in neuronal activity across the brain that are obscured by traditional trial averaging. To reconcile these observations, we use wide-field optical mapping to simultaneously record pan-cortical neuronal and hemodynamic activity in awake, spontaneously behaving mice.

Neuronal birthdate reveals topography in a vestibular brainstem circuit for gaze stabilization.

Across the nervous system, neurons with similar attributes are topographically organized. This topography reflects developmental pressures. Oddly, vestibular (balance) nuclei are thought to be disorganized.

A Genetic Engineering Toolbox for the Lignocellulolytic Anaerobic Gut Fungus .

Anaerobic fungi are powerful platforms for biotechnology that remain unexploited due to a lack of genetic tools. These gut fungi encode the largest number of lignocellulolytic carbohydrate active enzymes (CAZymes) in the fungal kingdom, making them attractive for applications in renewable energy and sustainability. However, efforts to genetically modify anaerobic fungi have remained limited due to inefficient methods for DNA uptake and a lack of characterized genetic parts.

Online Teaching Skills During the COVID-19 Pandemic and Beyond: One Curve We Do Not Want to Flatten.

The COVID-19 pandemic challenged physicians in academic medicine and clinician-educators in the classroom and at the patient bedside. Medical educators had to pivot overnight-adaptability was essential to providing quality medical education despite government shut-downs, accrediting body recommendations, and institutional limitations on clinical rotations and in-person meetings. Academic institutions faced multiple challenges in making the switch from in-person teaching to online learning.

Renal-hepatic-pancreatic dysplasia type 2: Perinatal lethal condition or a multisystemic disorder with variable expressivity.

Background: Renal-hepatic-pancreatic dysplasia type 2 (RHPD2) is a rare condition that has been described in the literature disproportionately in perinatal losses. The main features of liver and kidney involvement are well described, with cardiac malformations and cardiomyopathy adding additional variation to the phenotype. Many patients reported are within larger cohorts of congenital anomalies of kidney and urinary tract (CAKUT) or liver failure, and with minimal phenotypic and clinical course data.

The age-dependent immune response to ischemic stroke.

Stroke is a devastating cause of global morbidity and mortality. Ischemic brain injury triggers a profound local and systemic immune response that participates in stroke pathophysiology. In turn, this immune response has emerged as a potential therapeutic target.

Cannabinoid Hyperemesis Syndrome: Lighting Up an Emergency Department Near You.

Cannabis legalization may increase the rates of emergency department presentations and hospitalizations from Cannabinoid Hyperemesis Syndrome (CHS). This syndrome was first described nearly 20 years ago and has become increasingly common. Yet, for a variety of reasons, CHS is still an underrecognized cause of recurrent abdominal pain, nausea, and vomiting.