bluuebunny/crossref_metadata_2025 huggingface dataset:
Pro‐Survival Protein Kinase Cδ Signaling Cascades are Mediated by (−)‐Epigallocatechin Gallate (EGCG) Polyphenols
Authors: Sloan Alyssa L. , Daul Allison , Shor Audrey C.
Published: April 2020

We have previously demonstrated that the pro‐survival isoform of Protein Kinase C Delta VIII (PKCδVIII), forms complexes with ERK1/2 and Cyclin D1 and contributes to pro‐survival signaling cascades. Ultimately, neuronal death contributes to the Alzheimer’s Disease phenotype. Retinoic acid stimulation has proven to be effective in altering PKCδ signaling mechanisms involved in neuronal degeneration. (−)‐Epigallocatechin‐3‐gallate (EGCG), a polyphenol found naturally in green tea, serves as a potential treatment for neurodegenerative diseases. Properties of EGCG may control the expression of antioxidant enzymatic activity via PKCδ signaling. A synthetic, yet more stable and bioavailable, form of EGCG can be synthesized via peracetate protection (AcEGCG). The mediation of natural and synthetic EGCG on PKCδVIII signaling pathways has not yet been elucidated. This study sought to characterize the neuronal protection introduced by treating retinoic acid stimulated NT2 cells with EGCG and AcECGC. Retinoic acid stimulation induces alternative splicing of PKC, which leads to expression of the pro‐survival, PKCδVIII, isoform. A dosed response relationship between EGCG/AcEGCG (0–100 μM) treatment and activation of PKCδVIII signaling were considered. ERK1/2 and Cyclin D1 expression and complex formation with PKCδVIII were described. Studying the effectiveness EGCG polyphenols promotion of pro‐survival mechanisms in neurons may contribute to the development of neuroprotective therapeutic agents that could prevent neurodegenerative diseases such as Alzheimer’s Disease.
The effect of hand preference on skeletal asymmetry in human limbs
Authors: Eriksen Amandine B. , von Cramon-Taubadel Noreen
Published: April 2020

The study of asymmetry offers valuable insight into the biomechanical factors, such as hand preference, that influence development of the human body. Previous studies of human skeletal asymmetry often lack known handedness data and tend to presume right‐handedness without specifically analyzing upper limb elements. Here, we investigate differences in individual asymmetry (IA) in elements of the upper limb (i.e. humerus, radius) and lower limb (i.e. femur, tibia) from a modern sample of 40 males and females for whom hand preference was documented. The shape of these four bones was quantified using landmark configurations on 3D bone models. All possible distances between landmarks were calculated for the left and right sides of each bone and were used to calculate average IA for each individual bone. The results found that IA for the four bones was only correlated between the humerus and radius (r = 0.33, p = 0.038), suggesting that the upper limb does not always correlate with the lower limb as previously thought. Kruskal‐Wallis and Mann‐Whitney U tests found no significant differences in IA across sex or handedness groups for the limb bones but left‐handed males and females had higher left‐side dominance in the radius and tibia as compared to right‐handed individuals. Thus, the results suggest that handedness can affect asymmetry in the lower limb. Further addition of specimens, particularly left‐handed individuals, will elucidate the relative effects of handedness in shaping human skeletal asymmetry patterns.

Support or Funding Information

This was supported by funding from the Wenner‐Gren Dissertation Fieldwork Grant (Grant #9641), the Mark Diamond Research Fund (SP‐18‐19), and the 2017 Morris E. and Lucille R. Opler Dissertation Research Scholarship.
Essential Anatomy for General Surgery in the Undergraduate Medical Curriculum
Authors: Keim Sarah , Topping Daniel , Zumwalt Ann , McNary Thomas , Farias Anna , Granite Guinevere , Notebaert Andrew , Sanky Charles , Laitman Jeffrey , Reidenberg Joy S. , Lewis Steven , Brooks William , Royer Danielle , Martindale Jim , Harmon Derek , Hankin Mark
Published: April 2020

Introduction

To prepare medical students for clinical training and practice, it is critical to understand the anatomical knowledge considered most important for different clinical specialties.

Aim

To address this issue, a consortium of anatomists in the US and Canada is collecting data from clinical educators in General Surgery clerkships and electives to identify the anatomy they consider essential.

Methods

An IRB‐approved, online survey (Qualtrics, Seattle, WA) was used to assess the importance of 98 anatomical topics in seven body regions. The study first examined the percentage of General Surgery clinical educators (clerkship/elective directors and attending physicians) that considered each anatomical region important to their specialty. Second, the study examined the rank assigned to each anatomical topic using an ordinal scale from 1 (not important) to 4 (essential).

Results

At the time of abstract submission, data had been collected from 40 General Surgery clinical educators at 14 medical schools. The percentage of General Surgery clinical educators that considered each anatomical region important to their specialty were (highest‐to‐lowest): Abdomen (100%), Pelvis & Perineum (89.7%), Thorax (82.5%), Head & Neck (71.8%), Upper Limb (61%), Lower Limb (59%), and Back (51.2%). Further data analysis has identified the highest ranked anatomical topics in each body region for the General Surgery clerkship/elective.

Discussion and Conclusion

This database provides detailed information regarding the most clinically relevant anatomical topics as identified by General Surgery clinical educators. This information can aid in focusing preclinical learning to best prepare medical students for success in their undergraduate and graduate clinical experiences.
Comparison between Supplementation and a Diet High in Vitamins A, C, E on Inflammation and Oxidative Stress in Patients with Cardiometabolic Risk
Authors: Ortiz-Avila Omar , Campos-Arroyo Ana Gabriela , del Carmen López-Miranda María
Published: April 2020

Cardiometabolic risk refers to interrelated traditional risk factors for metabolic syndrome such as dyslipidemia, hypertension, obesity, insulin resistance, and hyperglycemia as well as behavioral factors such as physical inactivity, smoking, and unhealthy eating patterns. Family history, age, sex, and race/ethnicity also contribute to cardiometabolic risk. Currently Mexico has presented an increase in cases of obesity, according to the OCDE, Mexico is the second country, after the United States, with higher degree of obesity in the adult population. Oxidative stress and inflammation play a central role in the onset and development of many of the diseases that appear in patients with cardiometabolic risk, due to this an alternative in the treatment would be the use of antioxidants such as vitamins A, C and E. High dietary intake of vitamin C, carotenoids, and vitamin E have been associated with reduced risk of cardiovascular disease, cancer, and mortality, but these associations have not shown conclusive results. In addition, there is controversy between whether it is better to supplement these vitamins or include them in diet foods.

Therefore, the objective of this work was to compare the effect between foods and supplements with a high contribution of vitamin C, A and E on markers of inflammation and oxidative stress in patients with cardiometabolic risk. The sample selection is from voluntary subjects and consists of 30 people between 30 and 60 years of age who present cardiometabolic risk factors, which were divided into two groups, one received the vitamins in supplements and the other in the food of the diet for 90 days. At the beginning and the end of the treatment, anthropometric measurements, biochemical determinations such as glucose and lipid profile, as well as markers of inflammation (IL‐6 and TNF‐α) and oxidative stress (TBARS and Glutathione) were performed.

On average the patients was 33.4 years old and they had a BMI of 34.5. Women had a waist circumference of 88 cm and 102 cm for men which most were obese. In addition, patients had impaired fasting glucose levels (105.4 mg/dL) and low HDL levels (Men: 31.3 mg/dL; Women: 42 mg/dL). As they were patients with cardiometabolic risk presented oxidative stress and inflammation. The consumption of supplements showed a greater effect in reducing these parameters since were higher doses that can’t be achieved with diet foods. The results indicate that consumption of vitamins A, C and E in patients with cardiometabolic risk is a tool that can complement the treatment of these patients because it helps reduce oxidative stress and inflammation due to its antioxidant effects.

Support or Funding Information

This project was sponsored by the Instituto de Investigaciones de la Universidad de Morelia S.C.
A study of E. coli RNA polymerase‐Template interaction utilizing CRISPR/dCas9 protein
Authors: King Maxwell J.M. , Rohlman Christopher E.
Published: April 2020

This project focuses on sequence‐specific E. coli RNA polymerase transcription pausing using dCas9 protein. dCas9 is one type of Cas9 protein which is an RNA‐guided enzyme that cleaves DNA at specific locations. dCas9 lacks the ability to cut DNA or RNA. However, this dead‐Cas9 (dCas9) retains its ability to bind DNA at a specific location when guided by a complementary RNA molecule. In order to bind to desired location of DNA, dCas9 needs this small RNA that can guide it to bind at the targeted DNA sequence. When dCas9 binds to the DNA sequence, it blocks transcription, which is the process of copying DNA into RNA with the help of enzyme called RNA polymerase. The goal of this project is to investigate the structural and chemical interaction between dCas9, DNA and E. coli RNA polymerase at the point of the transcription blockade. A second goal of this project is to study the behavior of the E. coli RNA polymerase following a targeted pause in the transcription process
Effect of Chronic Temperature Acclimation on the Liver Proteome of Threespine Sticklebacks (Gasterosteus aculeatus)
Authors: Levitan Bryn Bo , Bates Alexandria Nicole , Kültz Dietmar
Published: April 2020

This study investigated the liver molecular phenotypes of two different populations of first generation lab‐reared threespine sticklebacks (Gasterosteus aculeatus) from northern California: a fully plated population from the Klamath River in Klamath, CA and a low plated population from Big Lagoon in Trinidad, CA. Temperature is one of the most influential abiotic factors affecting fish and this study gives insight into the molecular changes used to offset temperature stress in the liver. We constructed an assay library for the liver that consisted of 1,715 proteins, 5,897 peptides, 6,995 precursors, and 40,999 transitions with Skyline (MacCoss Lab). The assay library was constructed with samples from fish (N=22) of both populations after chronic warm, chronic cold, acute warm, and acute cold (Klamath population only) temperature stress experiments using data dependent acquisition (DDA) shotgun proteomics. This assay library was then used to compare the molecular phenotypes of Klamath and Big Lagoon stickleback livers after a three‐week exposure to either 7°C (cold), 15°C (control), or 25°C (warm). It will also be used to analyze acute temperature stress experiments in the future. Liver proteomes were extracted, trypsinized, and analyzed by gel‐free quantitative proteomics using liquid chromatography‐mass spectrometry (LC‐MS/MS). There were only 6 proteins with significantly different abundances between the Klamath and Big Lagoon populations (p < 0.05, fold change ± 2), suggesting similar molecular phenotypes between the two groups. There were 8, 141, and 234 proteins with significantly different protein abundances for comparisons of 7°C and 15°C, 15°C and 25°C, and 7°C and 25°C respectively (across both populations combined). Our results suggest that gradual acclimation to a warmer temperature, as opposed to a colder temperature, results in larger changes in relative protein abundance and gives insight into potential liver adaptations to sustained warmer temperatures.

Support or Funding Information

This study was funded by a grant from NSF (IOS‐1656371).
Constitutively Active Rheb Regulates Nuclear mTORC1 Activity and Function
Authors: Zhong Yanghao , Zhou Xin , Guan Kun-Liang , Zhang Jin
Published: April 2020

mTOR complex 1 (mTORC1) is a key signaling hub that regulates many fundamental cellular processes, including macromolecule synthesis, proliferation and autophagy. Abnormalities in mTORC1 signaling pathway are implicated in pathological conditions such as the progression of cancer and diabetes. Diverse signals can regulate mTORC1 activity and spatiotemporal regulation of mTORC1 has been suggested to play a crucial role in achieving high signaling specificity. Previously, a fluorescent mTORC1 activity reporter (TORCAR) revealed nuclear mTORC1 activity in live cells. However, the specific mechanisms that regulate nuclear mTORC1 activity and the functionalities of nuclear mTORC1 are unclear. In this study, we investigated whether and how Rheb, a key mTORC1 activator, is involved in regulating growth factor induced nuclear mTORC1 activity. First, we showed knockdown of Rheb largely suppressed growth factor stimulated nuclear TORCAR response. We further showed that Tuberous sclerosis complex subunit 2 (TSC2), a GAP for Rheb, was absent from the nucleus, and overexpressing TSC2 exclusively in the nucleus significantly inhibited nuclear TORCAR response, suggesting that Rheb is constitutively active in the nucleus. Our experimental data established a model of nuclear mTORC1 regulation and suggested Rheb is indispensable for nuclear mTORC1 activity. Our ongoing experiments include using phosphoproteomic experiments to identify the substrates of nuclear mTORC1 and RNAseq experiments to examine the emerging role of nuclear mTORC1 in controlling transcription in the nucleus.
In Silico Prediction of Cytochrome P450‐Based Drug‐Drug Interactions in Breast Cancer Treatment Regimens
Authors: Arrighi Scott , Hernandez Layrette , Deb Subrata
Published: April 2020

Introduction

Breast cancer is one of the most frequently diagnosed cancers in US. Its treatment regimens are complex as they involve premedications and concomitant medications, and can result in drug‐drug interactions (DDI). There are limited data available on cytochrome P450 (CYP)‐based drug interactions within the breast cancer regimens. The goal of the current study was to predict DDI between the drugs in the breast cancer treatment regimens.

Methods

Using the National Comprehensive Cancer Network (NCCN) guidelines the treatment regimens for breast cancer were identified. In silico DDI predictions were performed at steady state simulation using DDI module of the GastroPlus software provided by Simulation Plus Inc. The premedication and concomitantly administered drugs were evaluated as combinations with chemotherapeutic agents. Various enzyme inhibition kinetics parameters (e.g., Ki and EC50) required for simulation were obtained from the recent literature.

Results

Using the simulated and calculated gut and liver unbound perpetrator concentration during the steady state simulation, combinations of drugs showed differential DDI potential. Aprepitant, an antiemetic agent, showed moderate to strong inhibition when used with docetaxel, paclitaxel, abemaciclib and olaparib. In certain cases calculated liver perpetrator concentration showed a stronger inhibitory prediction of chemotherapeutic agents compared to simulated liver perpetrator concentration. Results obtained with netupitant varied from weak to strong inhibitory interactions with chemotherapeutic agents.

Conclusions

In silico analyses appear to confirm that breast cancer treatment regimens may interact with each other and influence plasma concentrations of chemotherapeutic agents. We conclude that toxicity or therapeutic failure from anticancer agents could be due to interactions within the breast cancer treatment regimens.

Support or Funding Information

The GastroPlus software 9.5 version was provided by Simulations Plus, Inc. (Lancaster, CA)
Protein Kinase C Activity is Increased in Human Coronary Smooth Muscle Cells following Exposure to 5‐FU Chemotherapy
Authors: Parr Shannon K. , Hammond Stephen T. , Baumfalk Dryden R. , Kunkel Olivia N. , Steele Catherine C. , Behnke Bradley J. , Ade Carl J.
Published: April 2020

Background

5‐Fluorouracil (5‐FU) is the third most commonly used chemotherapeutic agent used to treat cancer but is strongly associated with a dose‐limiting cardiotoxicity. Cancer patients treated with 5‐FU chemotherapy are at risk of cardiotoxicity that manifests as alterations in the myocardial circulation such as resting or exertional angina, arrhythmias, myocardial infarction, and coronary vasospasm. However, little is known about the primary signaling mechanisms that contribute to cardiotoxicity with 5‐FU. Recent work has suggested that the Protein Kinase C (PKC) family of kinases plays a role in altered vasoconstrictive responses in vascular smooth muscle following exposure to 5‐FU. Further, PKC signaling in other pathologies is known to be influenced by reactive oxygen species (ROS) and 5‐FU chemotherapy is known to promote the production of ROS. Therefore, we hypothesized that 5‐FU administration would increase PKC activity in human coronary smooth muscle cells (HCSMCs).

Methods

In vitro, HCSMCs were incubated with 5‐FU (7×10−3M) for 3h, 1h, and 10 minutes. Following the respective incubation periods, media was aspirated in control and 5‐FU groups and the HCSMCs were scraped, homogenized in lysis buffer, and analyzed for protein content. The activity of PKC was assessed by a PKC activity assay kit.

Results

Analysis revealed relative PKC activity was significantly increased in HCSMCs following 10 minutes of exposure to 5‐FU chemotherapy (6.52±0.36 versus 4.84±0.36; p=0.02) and was not different at 1 hour versus control and 3 hours versus control (1h 5.28±0.356 versus 4.84±0.36; p=0.82, 3h 5.67±0.36 versus 4.84±0.36; p=0.37).

Conclusions

Our findings suggest 5‐FU exposure acutely upregulates PKC activity in coronary smooth muscle cells immediately following drug administration and the PKC pathway may have a mechanistic role in the altered vasoconstrictive response to 5‐FU as previously shown. These findings are imperative given the limited knowledge of mechanistic pathways that lead to vascular damage following 5‐FU exposure. Future studies will focus on reactive oxygen species as a regulator of PKC activity and specific isoforms involved in this pathway.
Hepatocyte specific ablation of β and γ‐catenin leads to altered hepatocyte polarity and EMT induction
Authors: Pradhan-Sundd Tirthadipa , Singh Sucha , Bell Aaron , Monga Satdarshan Pal
Published: April 2020

A hallmark of epithelial cells is polarization. Like any other epithelial cell, hepatocytes in the liver show a unique polarity by forming several apical and basolateral poles within a cell. Polarization of hepatocytes is necessary for many functions and requires carefully orchestrated cooperation between cell adhesion molecules, extracellular matrix, cell junctions, cytoskeleton, and intracellular trafficking machinery. Loss of hepatocyte polarity is associated with various liver diseases including cholestasis.

Previously, we discovered that simultaneous deletion of adherens junction protein β and γ catenin in the mice liver led to cholestasis (Hepatology, 2017). However, the molecular mechanism that led to cholestasis in the absence of β‐ γ‐catenin remained unclear. To address this, we have developed a hepatocyte specific β and γ catenin conditional double‐knockout mice. Electron microscopy revealed dilation of bile canaliculi with significant reduction in microvilli in the liver of double knock out mice. IHC, protein and RT‐PCR analysis revealed loss of several hepatocyte polarity markers including CD10, ZO‐2, BSEP, and MRP2, increased fibrosis and epithelial‐mesenchymal transition in the liver. Remarkably, RNA‐seq analysis revealed over activation of TGFβ pathway in double knock out liver and blocking TGFβ pathway led to partial rescue of tight‐junctional proteins and cholestasis. Taken together, our findings suggest that β; γ‐catenin are critical to the maintenance of hepatocyte polarity and cholestasis development by regulating TGFβ signaling in hepatocytes. Profound understanding of the regulation of hepatocyte polarity by both β ‐and γ‐ catenin will be useful not only in understanding cholestasis but also in the context of liver development and pathophysiology.
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 Information

Supported 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.

Methods

To 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.

Results

ADGRL2 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.

Conclusions

Downregulation 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 Information

This 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 Information

This 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 Information

NIH 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 Information

Funding was provided by the National Institutes of Health R01EB022015 and the W.M. Keck foundation.
An Agent‐Based Model to Investigate Cellular Mechanisms of Vasculogenesis
Authors: Nikmaneshi Mohammad R. , Mohammadi Hamed , Munn Lance L.
Published: April 2020

To form new blood vasculature during development or tissue repair, endothelial cells self‐organize into primitive capillary plexuses by extending cell processes and migrating in the tissue. This complex process has been the subject of many experimental systems in vitro and in vivo, but the mechanisms responsible are poorly understood. To investigate the local cues that endothelial cells use to produce intricate vessel networks from a collection of disorganized single cells scattered in tissue, we developed an agent‐based mathematical model that explicitly tracks the location and migration of each cell in the tissue. By specifying the local rules that determine the direction and speed of each cell, we can explore cellular mechanisms that provide optimal network formation. The model includes four different computational layers and eleven cell signaling‐induced rules for endothelial cells. The computational layers include current locations of endothelial cells and their filopodia extensions and previous locations. We find that decreasing the influence of haptotactic path guidance reduces the density and formation rate of the vessel network. The simulated networks show good quantitative agreement with our in vitro experimental vasculogenesis assay.
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

Introduction

Between 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.

Aim

The 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.

Methods

Prior 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.

Results

The 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 Conclusion

Although 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.
Optimizing Vessel Normalization and Chemotherapies to Control Tumor Growth
Authors: Nikmaneshi Mohammad R. , Firoozabadi Bahar , Munn Lance L
Published: April 2020

The search for efficient chemotherapy drugs would benefit from a deeper understanding of the tumor microenvironment (TME) and its role in tumor progression. Because in vivo experimental methods are unable to isolate or control individual factors of the TME, and in vitro models often cannot include all the contributing factors, some questions are best addressed with systems biology mathematical models. In this work, we establish a multi‐scale mathematical model of the tumor microenvironment to simulate three‐dimensional tumor growth and angiogenesis and then implement the model for an array of chemotherapy approaches to control tumor progression. The chemotherapy approaches include: single anti‐cancer or anti‐angiogenic drug, combined anti‐cancer and anti‐angiogenic drugs, metronomic (low dose‐high frequency) anti‐cancer drug, and metronomic‐combined anti‐cancer and anti‐angiogenic drugs. We show that metronomic chemotherapy with one day frequency produces responses very similar to the higher frequency, low dose, but should result in lower toxicity. We further simulate different sequences of treatments to optimize combination anti‐angiogenic and chemotherapies. The computational results of chemotherapy performance in response to anti‐cancer and anti‐angiogenic drugs are in good agreement with experimental measurements.
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 Information

Experiments that lead to this poster were supported by NIH RO1 DK059888, DK055679 to AN. The authors declare no conflict of interest.