bluuebunny/crossref_metadata_2025_split huggingface dataset:
Encephalic Gray Matter macroscopic staining. An historical overview and three techniques comparison
Authors: Figueredo Luisa Fernanda , Quiroga Pedro , Ramirez David , Velasquez Catalina , Stozitzky Nicolas , Rueda-Esteban Roberto Javier 
Published: April 2020

Macroscopic staining in central nervous system anatomical specimens is a technique that allows obtaining better differentiation of multiple structures as the basal ganglia, thalamus, putamen, globus pallidus amongst others. The methods for staining are based on using the different components of the brain, mainly the lipids in white matter. When staining is pursued, these lipids join with reactants such as phenol, generating a “coat” that prevents the staining of white matter during the procedure, restricting it to the grey matter. The original process described by Mulligan can be modified with multiple reactants to generate a broad range of colors.Our objective is to describe the technical differences between three broadly used staining protocols: Roberts, Mulligan and Prussian Blue comparing the results between them according to the quality of the reactants used.A literature review in Medline for articles published in English until October 2017 was done. Regular terms were used, including: Brain, Encephalic, Cerebrum, Staining, Stained. And Medical Subject Headings, including: Brain [title] OR encephalic [title] OR cerebrum [title]) AND (staining [title] OR stained [title] OR stain [title] OR Staining and Labeling [majn]). A total of 511 articles were obtained. 484 were excluded and a total of 28 articles were included.For staining trials, three human brains from our laboratory collection previously preserved in 10% v/v formaldehyde aqueous solution were selected. Coronal and axial cuts were performed, and staining was randomly performed in the slices following the instructions of the original protocols proposed for each staining in two randomly created specimen’s groups: USP quality reactants and Analytical grade reactants. An additional modification was the use of tap water vs distilled water. The most important independent variable for us was a room temperature of 12 C.All the methods were replicable with good results. Technically, Prussian Blue presented a greater risk of white matter staining. However, this problem could be easily solved by extended immersion of 3 to 4 minutes in Mulligan’s solution rather than the original protocol for Mulligan’s Staining that suggest 2 minutes. In addition, the use of tap water instead of distilled water did not change results.Finally, according to our experience, the purity of the reactants can be lower than suggested in old protocols; comparisons between results of high‐quality reactants vs USP quality did not exposed significantly interference with the outcomes.
SPARC: A Comprehensive Single Neuron Molecular Phenotype Map of the Right Atrial Ganglionated Plexus in the Pig Heart
Authors: Moss Alison , Achanta Sirisha , Robbins Shaina , Turick Scott , Nieves Sean , Hanna Peter , Dacey Michael , Swid Mohammed A. , Ardell Jeffrey , Shivkumar Kalyanam , Schwaber James S. , Vadigepalli Rajanikanth 
Published: April 2020

As part of the NIH SPARC program efforts to study the intrinsic cardiac nervous system, we developed the first comprehensive molecular phenotyping data on the right atrial ganglionated plexus (RAGP) within the intrinsic cardiac nervous system of the pig. We collected hundreds of single neurons from the RAGP and assayed these for expression of a wide range of genes relevant to neuronal functions. The sinoatrial node (SAN) of 4 pigs were injected with FastBlue, a retrograde tracer, labeling neurons projecting to the SAN. The RAGP of those pigs were then collected and sectioned. Both SAN‐projecting and non‐SAN‐projecting single neurons in RAGP were collected through laser capture microdissection (LCM), allowing for spatial mapping of all collected samples. Over 400 single neurons were collected (n=4 animals) and each neuron was assayed for over 300 genes using high throughput microfluidic qPCR using BioMark. Neuronal phenotypes were distinguished by multivariate analysis showing patterns of network activity between multiple genes. Interestingly, these phenotypes show no spatial preferences within the RAGP. Our results revealed extensive combinatorial expression of neurotransmitters across the RAGP neuronal phenotypes. Additionally, there was a large overlap in expression profiles of SAN‐projecting and non‐SAN‐projecting neurons, without any single gene or module acting as a distinguishing marker between the connectionally labeled groups. Previous studies have focused on cholinergic and catecholaminergic processes, showing evidence for extensive protein expression of cholinergic markers in RAGP. Our findings are in stark contrast to these results and demonstrate high gene expression correlation between cholinergic and catecholaminergic markers such as tyrosine hydroxylase (Th) and choline acetyltransferase (ChAT) in single neurons. This finding suggests that cells are poised for a rapid shift in neurotransmitter signaling as well as the possibility for post transcriptional regulation of neuron phenotype plasticity. Our present findings significantly expand the list of neuromodulatory peptides and their receptors known to be expressed in RAGP. For example, neuropeptide Y and somatostatin showed distinct co‐expression patterns with their respective receptors with significant non‐overlapping expression of transmitters and cognate receptors across single neurons. Taken together, our results reveal a complex organization of neuronal networks within RAGP‐SAN complex that is not entirely governed by connectivity or spatial location, with combinatorial patterns of local paracrine networks with potential influence on cardiac function.Support or Funding InformationSupported by the NIH Common Fund SPARC Program award OT2 OD023848 and NIH NHLBI Multiscale Modeling award U01 HL133360.
Ready to Launch: Student Performance in a Fully Online Laboratory Pilot Course
Authors: Hill Cheryl A. , Greer Sean , Proffitt James , Stafford Amanda 
Published: April 2020

The undergraduate human laboratory course at the University of Missouri provides anatomical education to a large population of health sciences undergraduates. To meet demand, an interdisciplinary team developed and implemented a fully online laboratory section in the fall of 2019 to complement the established hybrid laboratory sections. The current laboratory course is hybrid with one weekly meeting and a substantial online component. The model‐based face‐to‐face lab component of the hybrid sections was replaced by online virtual labs using the 3d4Medical Complete Anatomy app. Students were provided with worksheets to accompany a curated series of screens within the app to replicate the models and stations used in the face‐to‐face labs. Weekly meetings were held via a video conferencing platform to provide additional practice, assistance and opportunities to discuss clinical applications. The purpose of this study is to analyze student performance and satisfaction in a fully online section of a human anatomy laboratory course.The study sample included students enrolled in the fully online lab section (n=10) and the established hybrid lab section (n=405) in the fall of 2019. Student performance data include pre‐course assessments, post‐course assessments and three course exams. Exams consisted of 50 multiple choice questions on tagged models or specimens (physical models and donor materials in the hybrid lab sections, digital 3D models in the online section), histology slides, and radiology images. Questions on the assessments and exams were consistent across lab sections. Scores were statistically compared between the two lab modalities. Other data also collected during the semester included demographic data, mid‐semester evaluations and end‐of semester evaluations.Late semester results indicate that the students enrolled in the online course have higher exam scores compared to students enrolled in the hybrid sections, which possibly reflect the high level of motivation of the students enrolled in the online course. Students in the fully online section have expressed frustration with the app used in lieu of the in‐class models. Data from the pilot course will be used to inform future course organizational decisions.
Adhesion G‐Protein‐Coupled Receptor L2 Expression is Lost in Colorectal Cancer but is Also Associated with Colonic Stem Cells
Authors: Bucar Edie , McWilliams Cecelia , Frey Mark 
Published: April 2020

Colorectal cancer (CRC) is driven by uncontrolled expansion and differentiation of crypt stem cells. We are testing the role of adhesion G‐protein‐coupled receptor L2 (ADGRL2), whose function has yet to be studied in the intestine, as a potential gatekeeper for proliferating colonic stem cells and renewal.MethodsTo assess receptor regulation during disease, mRNA levels were measured in matched normal and tumor specimens from human CRC. We corroborated findings by mining Gene Expression Omnibus (GEO) datasets and examined receptor modulation in response to growth arrest conditions (serum starvation and MAP kinase inhibition) in human CRC cell lines. We further interrogated ADGRL2 function using a stable inducible shRNA knockout line using SW480 cells and compared the gene expression of colonocyte markers in the induced ADGRL2 KO cells versus non‐induced cells. To assess possible inflammatory links, mice were given DSS colitis with 3% DSS in drinking water for 3 days and colons were collected on day 7 in the hyperproliferative recovery phase.ResultsADGRL2 was significantly and selectively reduced in tumors relative to adjacent matched normal tissue (5.14 fold, p < 0.0001). This was confirmed using two GEO datasets, one of which also revealed a pronounced loss in adenomas (3.82 fold, p < 0.0001). ADGRL2 was induced by growth arrest conditions in CRC cell lines, both by serum starvation (2.79 fold, p = 0.0115) and map kinase inhibition (5.59 fold, p = 0.0086). Knockdown in SW480 cells resulted in a loss of the colonic stem cell marker LGR5, while other markers for colonic cell types remained unchanged. Analysis of publicly available microarray data confirmed that ADGRL2 and LGR5 levels are associated in the colonic mucosa. Adgrl2 levels were suppressed in recovery from DSS colitis (1.74 fold, p < 0.0001), suggesting a role in restricting repair mechanisms.ConclusionsDownregulation during recovery from colonic injury, induction by antiproliferative stimuli, and association with LGR5 together suggest that ADGRL2 may have a role in orchestrating epithelial regeneration in the colon, potentially as a stem‐cell specific negative regulator. The substantial loss of ADGRL2 in human CRC adenoma and adenocarcinoma raises the possibility that ADGRL2 functions as a tumor suppressor. Thus, while modulation of ADGRL2 levels may mediate epithelial repair following injury, chronic loss could give way to uncontrollable stem cell expansion and loss of crypt architecture, leading to dysplasia and tumorigenesis.Support or Funding InformationThis work was supported by: NIH R01DK095004 and a Senior Research Award from the Crohn’s and Colitis Foundation (MRF). Support for EB includes The Saban Research Institute Predoctoral Intramural Funding Grant and The Roy E. Thomas Foundation Graduate Scholarship. Support for CM includes an Undergraduate Summer Research Fellowship from the Crohn’s and Colitis Foundation.
Assessing the Degree of Differentiation in Myotubes derived from Patients with GNE Myopathy
Authors: Sattler Kristina M. , Busam Sara , Crowe Kelly E. 
Published: April 2020

GNE Myopathy (GNEM) is an extremely rare autosomal recessive disease that causes muscle wasting due to mutations in the GNE gene. The GNE protein is important for the synthesis of the sugar sialic acid (SA), and such mutations lead to a decrease in SA. Therapies in development seek to restore SA to the muscle, but such therapies are difficult to quantify. A robust biomarker is vital for assessing changes in sialylation that would occur after a therapy, and our lab aims to use myotubes derived from GNEM patient converted myoblasts to do so. However, first, the extent of differentiation of these cells must be determined. If myotubes have not fully differentiated, data may be skewed. Therefore, in order to successfully determine an effective biomarker, we first sought to determine the extent to which cells have fully differentiated into myotubes. To do so, we determined the fusion index as well as expression of myosin heavy chain (MHC) and desmin via immunohistochemistry in myotubes from converted myoblasts. Here, we show the extent of differentiation of myotubes derived from GNEM patients as compared to those derived from their unaffected family members.Support or Funding InformationThis work was supported by funds from the Beta Beta Beta Research Scholarship Foundation Fund.
Altered Glycosidase Activities at Physiological pH in the Pathogenesis of Sepsis
Authors: Aziz Peter V. , Haslund-Gourley Benjamin S. , Heithoff Douglas M. , Westman Julia S. , Restagno Damien , Lewis Benjamin J. , Fried Jeffrey C. , Ilse Mai-Britt , Lübke Torben , Marth Jamey D. 
Published: April 2020

Glycosidases are hydrolytic enzymes that are primarily studied in the context of intracellular catabolic pathways within the lysosome. Reductions in circulating glycosidase activities have been linked to lysosomal storage diseases and are typically detected in the blood acidified to mimic lysosomal pH. There are also instances of lysosomal storage diseases linked to increased glycosidase activities in blood circulation wherein the mannose‐6‐phosphate‐dependent trafficking is rendered dysfunctional. In addition, changes in circulating glycosidase activities have been associated with other syndromes including cancer, arthritis, alcohol abuse, sepsis, and colitis. We recently discovered that glycosidases present in multiple cell types and the sera and plasma are involved in the aging of secreted and cell surface glycoproteins. The exo‐glycosidase activities of endogenous circulating glycosidases generate the stepwise loss of glycan linkages over time as glycoproteins age in circulation, sequentially exposing underlying glycan linkages starting with the removal of the terminally‐positioned sialic acids. More is known of the neuraminidases in this first step and the role of asialoglycoprotein lectin receptors that can bind and endocytose the previously underlying and cryptic galactose ligands. We have optimized the detection of glycosidases involving those with galactosidase, glucosaminidase, mannosidase, and fucosidase activities using fluorimetric substrates in blood serum and plasma at physiological pH 7.4. We found all four glycosidase activities significantly above background in the blood and plasma at normal basal levels among healthy mouse and human species. We also identify the source of these glycosidases using glycosidase‐deficient mouse strains. We further present these measurements of normality and origin in comparison with measurements made during the onset and progression of sepsis caused by different pathogens in mice and humans. Our findings to be presented include the determinations of specific activities of glycosidases in response to experimental sepsis in the mouse caused by each of the five different clinically‐derived bacterial pathogens, and the discovery of a specific change in glycosidase activity statistically linked to a poor outcome (death) in human sepsis patients.Support or Funding InformationNIH grant HL131474.NIH grant HL125352.
Real‐time pharmacokinetic and pharmacodynamic measurements of drugs within the brains of freely behaving rats.
Authors: Ploense Kyle L. , Dauphin-Ducharme Phillipe , Arroyo-Curras Netzahualcóyotl , Williams Serina , Schwarz Nitsan , Kippin Tod , Plaxco Kevin W. 
Published: April 2020

The drug cocaine evokes complex neurochemical responses that mediate their influence of neural circuits underlying behavioral control, such as the dopamine pathways that we now know drive reward anticipation and locomotor behavior. In contrast, the anesthetic drug procaine functions as both a local anesthetic in the periphery, and a general anesthetic when it reaches the brain, affecting breathing, heart rate, and locomotion. However, the time resolution with which existing methods can measure these drugs is orders of magnitude poorer than the resolution with which physiological responses to these drugs occur. In response to this problem, our group has recently developed a new technology, electrochemical aptamer‐based sensors (E‐AB sensors), which are the size of a human hair and can detect physiologically relevant concentrations of specific drugs in‐situ, in awake, freely behaving animals. Here, we tested this new technology on rats that have been administered either cocaine or procaine intravenously and measured the concentrations of these drugs within the lateral ventricle concurrent with monitoring locomotor activity. We successfully measured the concentration of cocaine and procaine every 10 s for 2 hours and generated a full pharmacokinetic and pharmacodynamic profile for these drugs within the lateral ventricle. As cocaine concentrations increased (from 0 to 5 μM), they directly corresponded with increased locomotor activity and stereotypy, whereas increased levels of procaine in the lateral ventricle coincided with decreased heart rate, oxygen saturation (SPO2), and locomotion. In conclusion, we have developed a novel, potentially revolutionary, technology that can measure the pharmacokinetics and pharmacodynamics of psychoactive drugs within the brains of awake, freely behaving animals.Support or Funding InformationFunding was provided by the National Institutes of Health R01EB022015 and the W.M. Keck foundation.
The Association Between Medical Students’ Preferred Study Resources and Exam Performance in an Integrated Human Structure Course
Authors: Hoffman Leslie , Chong Alexander 
Published: April 2020

IntroductionBetween textbooks, online materials, and the laboratory, there is no shortage of resources available to medical students to aid them in their study of gross anatomy and histology. With the multitude of resources available students may become overwhelmed with options. Furthermore, many resources vary in quality, and students learning anatomy and histology for the first time may not be able to discern high‐quality from low‐quality resources, leaving them unsure about which resources are most beneficial to their learning.AimThe purpose of the study is to examine the association between students’ exam performance and their preferred resources for studying anatomy and histology in an integrated Human Structure course.MethodsPrior to the first Human Structure Exam, students completed a guided reflection about their study strategies and preferred resources. After the exam students were divided into three groups (high‐performing, average, and low‐performing students), based on their exam performance. Reflections from students in each group were de‐identified and analyzed, focusing on the students’ response to the question, “Which resources have you found to be most helpful?” Researchers were blinded to students’ exam performance during analysis. Based on students’ responses, a comprehensive list of resources was created, and similar resources were subsequently grouped into categories. A chi‐square test of homogeneity was used to determine if there was an association between students’ exam performance and the types of resources they used. The protocol was approved by the Indiana University IRB.ResultsThe analysis included 197 students: 68 high‐performers, 66 average performers, and 63 low‐performers. The resource that students most frequently identified as “most useful” were lecture presentations, notes, or power points (n=101). Atlases (n = 69) and online resources such as websites (n=53) were also popular resources. A chi‐square test of homogeneity revealed no significant differences in the types of resources used by high‐performing, average, and low‐performing students (p>.05).Discussion and ConclusionAlthough there is no association between students’ exam performance and the types of resources they preferred to use, there may be differences in the way students are utilizing and engaging with these resources that impacts exam performance. We are currently undertaking further qualitative analysis of students’ self‐reported study strategies to discern how students used the resources, and whether differences in study strategies impacts exam performance. The findings of this analysis may be useful for advising students on how to utilize resources most effectively.
Differential Regulation of Intestinal Epithelial Intercellular Adhesion and Barrier Function by Desmosomal Cadherins
Authors: Raya-Sandino Arturo , Kusters Dennis H.M. , Luissint Anny-Claude , Conway Daniel E. , Narayanan Vani , Hagen Susan J. , Smith Kyle H. , Flemming Sven , Garcia-Hernandez Vicky , Yulis Mark , Parkos Charles A. , Nusrat Asma 
Published: April 2020

Desmosomal cadherins mediate intercellular adhesion and provide mechanical strength to tissues. Intestinal epithelial cells express desmosomal cadherins Desmoglein‐2 (DSG‐2) and Desmocollin‐2 (DSC‐2). To explore the relative contribution of these cadherins in mediating intercellular adhesion of intestinal epithelial cells, we generated inducible intestinal‐epithelia specific (Villin‐CreERT2) Dsg‐2 and Dsc‐2 knockdown mice (Dsg‐2ERΔIEC; Dsc‐2ERΔIEC). While intestinal mucosal architecture was maintained in Dsg‐2ERΔIEC and Dsc‐2ERΔIEC mice, ultrastructural changes in desmosomal plaques and widened intercellular spaces were observed in these mice compared to littermate floxed control mice. Functional analysis revealed increased paracellular permeability to FITC dextran supporting compromised epithelial barrier function. Interestingly, Dsc‐2ERΔIEC mice showed reduction in desmosome length while Dsg‐2ERΔIEC animals exhibited a higher FITC dextran permeability, suggesting differential dominant roles of DSG‐2 in controlling intestinal epithelial barrier function and of DSC‐2 in regulating intercellular adhesion. Additionally, knockdown of these cadherins in‐vitro in epithelial cells resulted in decreased cell‐cell adhesion and compromised barrier function. Analysis of desmosome mechanical strain using DSG‐2 and DSC‐2 tension sensors revealed that loss of DSC‐2 increased intermediate filaments tension while the loss of DSG‐2 did not show any change in cytokeratin tension. These findings provide new insight on the relative contribution of DSG‐2 and DSC‐2 in controlling intestinal epithelial intercellular adhesion and barrier function.Support or Funding InformationExperiments that lead to this poster were supported by NIH RO1 DK059888, DK055679 to AN. The authors declare no conflict of interest.