bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential Role of Toll‐like Receptors in Elicitation of Cardiac Innate Response to IL‐10
Authors: Bagchi Ashim , Akolkar Gauri , Mandal Soma , Gao Xiaoling , Yang Xi , Singal Pawan
Published: June 2021

Pattern recognition receptors such as toll‐like receptor 2 (TLR2) and 4 (TLR4), are associated with myocardial ischemia/reperfusion (I/R) injury. Recently, it was suggested that TLR2 is detrimental whereas TLR4 promotes IL‐10‐mediated cardiac cell survival. However the mechanism of molecular balance between these two innate signaling molecules has not been elucidated. We explored the significance of these TLRs in response to IL‐10 in myocardial I/R injury using ex‐vivo, knockout (KO) and shRNA approaches. The ex‐vivo myocardial I/R injury model showed a marked expression of TLR2 and studies in the IL‐10 gene KO (IL‐10‐/‐) heart indicated a negative regulation of TLR2 by IL‐10. However, 40min reperfusion with IL‐10 after ischemia triggered TLR4 elevation. Inhibition of TLR4 activity using MyD88‐shRNA suggests a MyD88 adaptor molecule dependent activation of TLR4. Increased interleukin‐1 receptor‐associated kinase‐M (IRAK‐M) during I/R injury upregulates IRAK‐2, indicating IRAK‐M/IRAK‐2 requirement in TLR2 signaling. IL‐10 altered these changes significantly, suggesting that IL‐10 dissociates IRAK4 into IRAK 1. Circulating and myocardial levels of TNF‐α were higher in hearts with I/R injury. Consequently, TLR2‐mediated TNF‐α gene activation led to increased apoptosis by TLR2‐mediated IRAK‐M/IRAK‐2 activation. IL‐10 reduced the TNF‐α receptor‐associated increase in TRAIP/TRADD‐induced cell apoptosis during ischemia injury which led to an increase in IL‐1β to mitigate TGF‐βRII‐mediated fibrosis. Our results suggest that this cytokine may be a key therapeutic molecule in restoring heart health from ischemia injury via TLR4 innate signaling pathway (supported by CIHR).
Inhibitors of the Renin‐Angiotensin System (RAS) Completely Prevents Cardiac Hypertrophy (CH) Induced by Ischemic Renal Injury (IRI) via Angiotensin II (AngII)/Toll‐Like Receptors (TLR) Cross‐Talk
Authors: Abrahão Mariana , Monnerat‐Cahli Gustavo , Medei Emiliano , Carneiro‐Ramos Marcela
Published: June 2021

Objectives

The cardio‐renal syndrome comprises a set of pathophysiological kidney‐heart interactions. Renal injury promotes release of inflammatory cytokines (CTK), which may act through cardiac TLR and lead to CH, as well as AngII. This study aims to investigate a possible interaction between TLR and RAS in CH model induced by IRI.

Methods

C57BL/6 male mice (n=84) treated with Losartan (Los‐10 mg/kg) or Enalapril (Ena‐40 mg/kg) were subjected to surgical occlusion of left renal pedicle and kept under observation for 20d. IRI, CH and systolic blood pressure (SBP) were assessed by morphologic, molecular and functional parameters, as well as tail‐cuff plethysmography and electrocardiography (ECG) before and after surgery. Serum/cardiac RAS components, TLR2/TLR4 and inflammatory CTK were evaluated by Real‐Time PCR, protein expression and ELISA.

Results

The successfully‐performed IRI induced an enhancement of serum IL‐6, TNF‐a and IFN‐y (p<0.001) and did not promote SBP alteration. CH was observed after 12d of reperfusion, when cardiac AT1, ACE2, TLR2/TLR4 levels were increased (p<0.001). Los/Ena prevented CH (p<0.001) without changing SBP and modulated serum AngII and CTK levels (p<0.05). Also, ECG showed an improvement in cardiac function.

Conclusion

The presented data shows that RAS inhibition is able to completely prevent CH via regulation of cardiac TLR and serum AngII/CTK levels, suggesting the existence of a key cross‐talk between TLR and RAS in CH induced by IRI. Financial Support: FAPESP; CNPq.
Interpretation of the Genome in Synchronized Chlamydomonas Cells
Authors: Merchant Sabeeha , Blaby Ian , Strenkert Daniela , Coku Shawn , Pellegrini Matteo , Zones Matt , Umen James
Published: June 2021

Chlamydomonas has served for over half a century as a reference organism for fundamental discoveries in photosynthesis. Cultures of Chlamydomonas are readily synchronized by alternating light‐dark cycles. We sampled synchronized cultures of Chlamydomonas over a 24 h period to reveal highly coordinated expression of sets of genes encoding individual complexes or pathways. The density of sampling permits us to resolve closely spaced events to reveal that the expression of the nucleus‐encoded subunits of the proton pumping complexes precedes the expression of the photosynthetic reaction centers and their associated light harvesting complexes, which are themselves very tightly coordinated. The separation of expression of genes encoding photosynthetic metabolism from those encoding respiratory metabolism allows us to assign function in the Calvin‐Benson vs. oxidative pentose phosphate pathway to genes encoding isoforms of the same enzyme. The expression profile shows evidence for transient photo‐oxidative stress at the transition from dark to light and more sustained stress towards the end of the light cycle. Candidate regulatory RNAs have been identified as well.
Production of Oil in Plant Vegetative Tissues
Authors: Dyer John , Yurchenko Olga , Park Sunjung , Gidda Satinder , Cai Yingqi , Shockey Jay , Goodman Joel , Chapman Kent , Mullen Robert
Published: June 2021

Synthetic biology is an emerging area of science focused on the development of well‐defined molecular components that can be assembled and utilized for rational engineering design. In many cases, the process is geared towards production of high‐value compounds, and in biofuels research, a major goal is to maximize the amount of oil that can be recovered from plants. While seeds are the traditional source of plant oil, we and others are considering the engineering of oil in plant vegetative tissues. The rationale is that the biomass of plants is dominated by leaves and stems, and as such, production of even modest amounts of oil in these tissues may significantly increase the amount of oil recovered from plants. In this seminar I will describe a variety of approaches that we are using to increase the steady‐state amount of oil in plant leaves, including enhancement of the mechanisms for oil synthesis and disruption of processes for oil breakdown. Furthermore, we have recently identified proteins involved in lipid droplet biogenesis and compartmentation, which provide additional tools for modulating the packaging and storage of lipids in plant cells. Collectively, these studies define a growing set of molecular components that can be used for lipid modification. The results of these studies are informing not only the engineering of oil content in plant leaves, but also providing new insights to oil production in plant seeds. Implications for both food and fuel will be discussed.
Cryo‐EM at Near‐Atomic Resolution of Bacterial and Host Filaments
Authors: Egelman Edward
Published: June 2021

Large amounts of the proteins found in biology are in the form of helical polymers. This is as true for viruses as it is for bacterial, archaeal and eukaryotic cells. Unfortunately, unless a helical polymer has exactly 2, 3, 4 or 6 subunits per turn, it cannot be crystallized so that every subunit is in an equivalent environment. This has greatly reduced our ability to study helical polymers at atomic resolution. New advances in cryo‐EM, such as direct electron detectors and robotic microscopes, have recently given us the ability to reach near‐atomic resolution almost routinely for many protein and nucleoprotein polymers. I will focus on bacterial polymers that play a key role in pathogenesis, including pili, flagellar filaments, and a Type 6 Secretion System, to illustrate the remarkable advances that are now possible in the structural determination of protein filaments. One of the interesting conclusions from these studies is that very small changes in amino acid sequence in conserved building blocks, such as bacterial flagellin or Type IV pilin, can lead to very large changes in quaternary structure. This has been an under‐appreciated mechanism in evolutionary divergence.
Nutrient Regulation of Signaling & Transcription by O‐GlcNAcylation
Authors: Hart Gerald
Published: June 2021

O‐GlcNAcylation of nuclear and cytoplasmic proteins is a major sensor of cellular nutrient status, and has extensive crosstalk with phosphorylation and other post‐translational modifications. This extensive crosstalk regulates transcription, signaling and cellular metabolism in response to nutrient status. O‐GlcNAcylation plays a fundamental role in gene transcription at many levels, including regulation of the basal machinery, as well as modifying the interactions and localizations of transcription factors. O‐GlcNAc is also part of the histone code. Prolonged excess O‐GlcNAcylation, as occurs in diabetes, underlies fundamental mechanisms of glucose toxicity. Abnormal O‐GlcNAcylation is associated with neurodegenerative disease, and is elevated in most types of cancer. Over one‐half of all kinases are both modified and many are regulated by O‐GlcNAcylation. O‐GlcNAcylation either inhibits or activates, depending upon the kinase, and can alter substrate specificity. Hyper‐O‐GlcNAcylation of mitochondrial proteins in diabetic tissues contributes directly to mitochondrial dysfunction. Mitochondrial O‐GlcNAc transferase (OGT) is strikingly elevated and mis‐localized in cardiac mitochondria from diabetic rats. O‐GlcNAcylation is very abundant at nerve terminals, where it is highly enriched on synaptic vesicle proteins, and appears to play a direct role in learning and memory. Focused, inducible knock out of OGT in adult brain neurons produces a satiety defect and a morbidly obese mouse within only three weeks. Supported by NIH R01CA42486, R01DK61671; N01‐HV‐00240; P01HL107153 and the Patrick C. Walsh Prostate Cancer Research Fund. Dr. Hart receives a share of royalty received by the universityon sales of the CTD 110.6 antibody, which are managed by JHU
A New Look at Transcription‐Coupled DNA Repair
Authors: Nudler Evgeny , Epshtein Vitaly , Kamarthapu Venu , Svetlov Vladimir , McGary Kathleen
Published: June 2021

Nucleotide Excision Repair (NER) is a complex process that can detect a wide variety of DNA damage and is conserved throughout evolution. Transcription Coupled Repair (TCR) is a sub‐pathway of NER, which operates to repair the template strand of expressed genes faster than the rest of the genome. RNA Polymerase (RNAP) stalled at DNA lesions recruits NER enzymes to the damage site, suggesting an important role of RNAP in identifying DNA damage. Recently, we described a new TCR pathway, in which the NER enzyme UvrD plays the central role in assisting RNAP to initiate TCR. I will discuss the tradeoff between the new and existing TCR pathways, how and when each of them operates to repair DNA damage in E. coli, and the necessity of pervasive transcription in the maintenance of genome integrity.
Membrane Proteins ‐ the Lipid Connection
Authors: Robinson Dame Carol
Published: June 2021

Lipids are critical components of membranes and yet their precise composition and effects on membrane‐embedded protein complexes are often difficult to define. Using mass spectrometry I will show how we can add lipids and quantify their effects on the stability of membrane protein complexes using unfolding experiments. I will also show how results from these experiments inform about suitable solution conditions for crystallography and function. Turning to the endogenous lipid cohort that surrounds a membrane protein I will show how we can define these lipids and demonstrate their importance for function.
Structural Mechanisms of PI3K and PTEN Regulation
Authors: Williams Roger , Masson G. , Vadas O. , Burke J. , Perisic O.
Published: June 2021

The products of the phosphoinositide 3‐kianses (PI3Ks) have essential roles in intracellular signalling and sorting. Using X‐ray crystallography and hydrogen/deuterium exchange mass spectrometry (HDX‐MS) have enabled us to understand mechanisms whereby the PI3Ks and the lipid phosphatase PTEN are activated. HDX‐MS has allowed us characterise protein/protein and protein/membrane interactions for states inaccessible to X‐ray crystallography, and it has provided information about the dynamics of structures.

Two sites in the intrinsically disordered tail of PTEN have the ability to to switch its substrate specificity from lipid membranes to soluble substrates. The structural mechanism that regulates the enzyme involves the interaction of both the C2 domain and the lipid phosphatase domain with the C‐terminal tail in phosphorylation‐dependent manner.

The p110γ/p101 heterodimeric PI3K is activated downstream of GPCRs by association with Gβγ heterodimers, and HDX‐MS has shown that the p110 helical domain is central to this and other PI3K regulatory influences. The p101 regulatory subunit protects the helical domain, while lipid membrane association exposes it. Membrane binding enables the p110γ/p101 heterodimer to engage Gβγ heterodimers on membranes, using both p110 and p101 subunits.

The combination of these methods has enabled us to explore regulation of the broad family of enzymes related to PI3Ks.
Mechanisms of FGF‐Mediated Morphogenesis
Authors: Marcucio Ralph
Published: June 2021

Signaling by Fibroblast growth factors (Fgf) regulates many aspects of vertebrate development. During facial development, Fgf signaling helps regulate morphogenetic processes that control formation of the jaw skeleton. Using an Fgf8 allelic series of mice with graded levels of Fgf8 expression, we have demonstrated the requirement for Fgf8 signaling during facial development. However, the cellular and molecular mechanisms that Fgf signaling utilizes to direct morphogenesis are less clear. To address this, we turned to the chick system and infected embryos with retroviruses that encode either Fgf8, or a constitutively activated FgfR2, which causes craniosynostosis in humans. We determined that activation of the Fgf pathway led to mid‐facial hypoplasia accompanied by widening of the mid‐face. These morphologies were associated with decreased cell proliferation and increased expression of Sprouty's, Dusp's, and Spred's. We also observed that neural crest cells are polarized with respect to the sub‐cellular localization of the Golgi apparatus, and after activation of the Fgf pathway with either virus this polarity was disrupted. This disruption was associated with the extent of malformation present in the embryos. The Golgi apparatus is located adjacent to the nucleus in the leading edge of moving cells suggesting that oriented cell movement is required for normal morphogenesis. We are now testing how directed cell movements may contribute to morphogenetic processes, and our preliminary data suggest that forces exerted on the extracellular matrix may play a role in this process. In summary, a series of cellular processes such as proliferation and polarization appear to contribute to the emergent properties of developing systems during facial morphogenesis.
Substrate Recognition in Lantibiotic Biosynthesis
Authors: van der Donk Wilfred
Published: June 2021

The genome sequencing efforts of the first decade of the 21st century have revealed that another major class is formed by ribosomally synthesized and post‐translationally modified peptides (RiPPs). These molecules are produced in all three domains of life, their biosynthetic genes are ubiquitous in the currently sequenced genomes, and their structural diversity is vast. Lantibiotics are examples of this growing class. These peptides are post‐translationally modified to install multiple thioether crosslinks by dehydration of Ser/Thr and subsequent conjugate addition to the dehydro amino acids by Cys thiols. During their biosynthesis, a single enzyme typically breaks 8‐16 chemical bonds and forms 6‐10 new bonds with high control over regio‐ and chemoselectivity. This presentation will focus on how the substrate peptides are recognized by the synthetases and how the enzyme orchestrates the various reactions to generate a single product.
A Unified Model Describing The Architecture And Creation Of Promoters And Enhancers
Authors: Lis John , Core Leighton , Martins Andre , Danko Charles , Siepel Adam , Booth Gregory , Duarte Fabiana , Mahat Dig Bijay
Published: June 2021

Promoters and enhancers have been conventionally regarded as structurally and functionally distinct genomic entities. Nonetheless, in mammals, they share many features, including divergent transcription and common transcription factors. Here, we examine the architecture of transcription initiation through comprehensive mapping of transcription start sites (TSSs) in human cell lines. Using a nuclear run‐on protocol called GRO‐cap, which captures TSSs for both stable and unstable transcripts, we conduct detailed comparisons of thousands of promoters and enhancers. These analyses reveal a common architecture of initiation, including tightly spaced (110 bp) divergent initiation, similar frequencies of core‐promoter sequence elements, highly positioned flanking nucleosomes, and two modes of transcription factor binding. Post‐initiation transcript stability provides a more fundamental distinction between promoters and enhancers than patterns of histone modifications, transcription factors or co‐activators. These results support a unified model of transcription initiation and architecture at promoters and enhancers. We have now investigated how these patterns of divergent transcription are generated on enhancers in both Drosophila and mammalian cells. These new results will be presented and the implications of these findings on genome function and evolution will be discussed.
Visualizing Functional Motions of Membrane Transporters at an Atomic Resolution
Authors: Tajkhorshid Emad
Published: June 2021

Large‐scale conformational changes are central to the function of membrane transporters. Description of these structural changes, however, requires sampling high‐dimensional free energy landscapes that are inaccessible to experimental techniques and conventional computational methods. Combining advanced molecular simulation techniques and free energy methods, guided by experimental data, we have recently developed a novel computational approach that, while expensive, has been the most efficient way to describe large‐scale structural transitions in membrane transporters [PNAS 110:18916‐21 (2013); JCTC 10: 2866–80 (2014)]. The approach is based on simulations of large macromolecular systems preserving realistic representations of the systems in explicit membranes. Here we describe the application of the methodology to the study of several classes of membrane transporters, in order to characterize the inter‐conversion of these molecular devices between the major conformational states necessary for their function, to characterize the free energy profiles associated with these transitions, and more importantly how chemical details such as ion/substrate binding drastically modulate the energy landscapes. The results of these simulations elucidate highly relevant mechanistic details of the function of membrane transporters providing a detailed structural basis for the experimentally observed phenomena.
Mechanoregulation of Human Neutrophil Host Defense and Survival
Authors: O'Brien Xian , Elisseou Nicholas , Flores Estefany , Patel Dipan , Morrissette Cole , Loosley Alex , Reichner Jonathan
Published: June 2021

Neutrophils are an essential component of the inflammatory response, acting as the first responders to injury and infection. Because they are able to migrate into any tissue in the body, they necessarily encounter different physical microenvironments. Neutrophils traveling through different tissues encounter distinctive mechanical cues that affect their morphology, motility, and function. To understand how mechanosensing affects the phagocytic and antimicrobial functions of primary human neutrophils, we examined dectin‐mediated, Fcγ‐mediated. and complement‐mediated phagocytosis, the phagocytosis of apoptotic bodies, markers of respiratory burst and degranulation, IL‐8 production, NETosis, and cell survival on fibronectin coated subtracted of differing compliance. While respiratory burst and IL‐8 production were independent of substrate stiffness, we found a mechanoregulatory component to neutrophil degranulation, NETosis, and cell survival. We additionally characterize mechanosensitive differences in phagocytic receptor function and identify an oppositional regulatory role for Rho Kinase. These data provide clear evidence that neutrophil host defense and survival are directly affected by mechanical cues in the tissue microenvironment.
Constitutive and Antigen‐Induced Secretion of Cytokines by Peripheral Blood Mononuclear Cells of Tuberculosis Patients
Authors: Mustafa AbuSalim
Published: June 2021

Cytokines play a major role in protection against and pathogenesis of tuberculosis. Generally, T‐helper (Th)1 and pro‐inflammatory cytokines are considered protective, and anti‐inflammatory and Th2 cytokines are responsible for pathogenesis of tuberculosis. In order to study the release of various cytokines in response to a variety of antigenic stimuli, the in vitro secretion of cytokines was assessed using peripheral blood mononuclear cells from tuberculosis patients (diabetic and non‐diabetic) and healthy subjects in response to various mycobacterial antigens, including whole cells, culture filtrate, cell walls and pools of synthetic peptides corresponding to M. tuberculosis‐specific genomic regions, i.e. the regions of differences (RDs). The results showed that the concentrations of antigen‐induced Th2 cytokines were low/undetected and the pro‐inflammatory cytokines were non‐discriminatory. However, with regard to the Th1 and anti‐inflammatory cytokines, the antigens could be divided into two groups; the first group showed Th1‐bias (culture filtrate, RD1, RD5, RD7, RD9, RD10 and RD15), and the second group had anti‐inflammatory‐bias (whole bacilli and cell walls of M. tuberculosis, RD12 and RD13). Interestingly, the RD1 peptide pool induced the strongest Th1‐bias, and the addition of RD12 and RD13 peptides to the cultures suppressed the secretion of RD1‐induced Th1‐cytokines. Furthermore, when data were compared between diabetic and non‐diabetic TB patients, there was a shift towards pathologic (Th2/anti‐inflammatory) cytokines in diabetic TB patients, which may explain, at least in part, a faster deterioration in clinical condition of diabetic TB patients.

Supported by Kuwait University Research Sector grants MI01/10 and SRUL02/13.
Alcohol Exacerbates Liver Injury and Fibrosis in Mice With Liver‐Specific Deficiency of Augmenter of Liver Regeneration
Authors: Kumar Sudhir , Dangi Anil , Gandhi Chandrashekhar
Published: June 2021

Augmenter of liver regeneration (ALR) protein is expressed predominantly by hepatocytes in the liver, and is essential for their mitochondrial function. Liver‐specific ALR knockout (ALR‐L‐KO) mice develop accelerated steatohepatitis. Our aim was to investigate alcohol‐induced pathology in KO mice. WT or KO mice were fed isocaloric or 4% ethanol diet for 4 weeks. Ethanol‐fed KO mice showed retarded growth, excessive liver injury, increased serum ALT, but lower hepatic triglycerides as compared with WT ethanol‐fed mice. Whereas ethanol increased expressions of acetyl‐CoA carboxylase, fatty acid synthase and sterol regulatory element‐binding transcription factor 1 in WT mice, they were dramatically reduced in KO mice. Additionally, while expressions of alcohol dehydrogenase 1, acetaldehyde dehydrogenase 1 and Cyp2E1 increased in ethanol‐fed WT mice, they decreased in KO mice. These pathologies in KO mice were accompanied by increased oxidative stress, TNFα and TGFβ, and excessive fibrosis; WT mice increased TNFα but did not develop fibrosis. Hepatic ALR was also lower in humans with advanced alcoholic liver disease (ALD) and frequency of several single nucleotide polymorphisms was increased in ALD subjects compared to normal population. Our findings indicate that ALR protein deficiency causes exacerbation of alcohol‐induced liver injury and excessive fibrosis, and abnormality in ALR protein or deficiency may be an important mechanism of advanced ALD in humans, which occurs in about 30% of the population

Grant support: Supported by a VA Merit Review Award (1IO1BX001174) and NIH (PO1AIO81678 and R21AA020846).
Receptor Interacting Protein Kinase 3 Deficiency Exacerbates Cholestatic Liver Injury in Mice
Authors: Woolbright Benjamin , Williams C , Bajt Mary‐Lynn , Ding Wen‐Xing , Jaeschke Hartmut
Published: June 2021

Obstructive cholestasis leads to acute and chronic liver injury. In the bile duct ligation (BDL) model, injury occurs through necrosis, and is mediated by recruited neutrophils. Receptor interacting protein kinase 3 (RIP3) is an integral mediator of programmed necrosis. Depletion of RIP3 protects against acetaminophen hepatotoxicity, and alcoholic steatohepatitis, suggesting it might be a major mediator of necrosis in the liver. The purpose of this study was to determine if RIP3 was induced during cholestatic liver injury, and to further determine if deficiency of RIP3 protects against BDL. BDL or sham surgery was carried out on wild type (WT) C57Bl/6 or RIP3‐/‐ mice and liver injury was assessed 24 and 72 hours later. RIP3 protein was induced after BDL in murine liver. Although sham WT and RIP3‐/‐ mice were similar, RIP3‐/‐ mice had significantly higher plasma ALT values than WT mice after BDL. Histological analysis confirmed the increase in injury using both H&E and TUNEL stains. RIP3‐/‐ mice also had significantly greater neutrophil infiltration than WT mice post BDL. This was despite the fact multiple genes associated with inflammation during cholestasis were not different between WT and RIP3‐/‐ mice, and there were no differences in circulating neutrophil counts in RIP3‐/‐ and WT mice before or after BDL. Interestingly, injury 6 hours post BDL was similar between groups; however, there was increased neutrophil infiltrate in the RIP3‐/‐ mice, indicating the increase in neutrophils occurred before the increase in injury. In conclusion, these data indicate RIP3‐/‐ mice are more susceptible to cholestatic liver injury, likely through enhanced and sustained accumulation of cytotoxic neutrophils.
NIFK Promotes Lung Cancer Metastasis through Runx1‐dependent Repression of Casein Kinase 1α to Activate Wnt/β‐catenin Signaling
Authors: Lin Tsung‐Chieh , Su Chia‐Yi , Tsai Ming‐Daw , Hsiao Michael
Published: June 2021

Ki‐67 is the most commonly used biomarker in clinical practice to predict prognosis and therapeutic strategies in cancer patients. NIFK, known as an important Ki‐67 interacting protein, whose role in cancer is still largely uninvestigated. Here we report pro‐metastatic role of NIFK in lung cancer. In large patient cohort analysis from TCGA public database, significant positive correlation between NIKF and Ki‐67 expression was found in over ten cancer types. By ranking the prognostic predictive ability of NIFK in various cancer types, we found that NIFK has the strongest prognostic impact on lung cancer patients. High NIFK expression was associated with poor prognosis and tumor metastasis in lung cancer. Furthermore, overexpression of NIFK enhanced migration and invasion ability and in vivo metastasis, whereas knockdown of NIFK reduced cell migration and metastasis in lung cancer cell lines. Microarray analysis identified that casein kinase 1α (CK1α), the suppressor for pro‐metastatic TCF4/β‐catenin signaling, was downregulated by NIFK. Complementarily, CK1α was upregulated upon NIFK knockdown. Further repression of CK1α expression in cells of NIFK knockdown restored TCF4/β‐catenin transcriptional activity, cell migration, and metastasis. Besides, Runx1 was identified as transcription factor of CK1α, and was shown to be negatively regulated by NIFK. Taken together, our results demonstrate the prognostic value of NIFK, and suggest that it is required for lung cancer metastasis through Runx1‐dependent CK1α repression, leading to the TCF4/β‐catenin signaling activation. (This study was supported by Academia Sinica to Dr. Michael Hsiao.)
Reaction Time as a Physiological Process in Fourth Grade Students
Authors: Barrett Emily , Fagg Breanna , Anthis Taylor , Harpenau Olivia , Gurovich Alvaro
Published: June 2021

This project was designed to educate fourth grade students on the importance of understanding physiology as a sub‐project of the American Physiological Society's PhUn Week. The fourth graders at Dixie Bee Elementary school were exposed to the importance of reaction time and how proprioception and nerve conduction velocity impact reaction time in all individuals. The initial information was presented in an interactive education seminar and then demonstration occurred using applied technology (Biopac MP40). The Biopac MP40 is an interactive tool that helps to show data via the electrical signal released by the nerve and picked up by electrodes, all integrated on a laptop computer. Reaction time activity was obtained synchronizing two signals by Biopac MP40: 1) acoustic signal, via headphones, and 2) electric signal from finger extensors by placing the electrodes on the forearm. The MP40 system integrates both signals determining reaction time. The students were then challenged to perform their reaction time with the Biopac MP40 system by themselves to record data. Finally, students analyzed their own data to contribute to the overall discussion about physiological processes. The students had a wonderful time and were able to describe the idea of proprioception and reaction time at the end of the activity. They documented their slowest and fastest reaction times and used these data on their subsequent sciences classes to plot and analyze data.

Supported by IU AHEC 14/15 #PIU081 and APS PhUn week program
Educational outreach as a simple, yet effective, service learning opportunity for exercise science undergraduate and graduate students
Authors: Merritt Edward , Merritt Bronwyn
Published: June 2021

Few opportunities exist for field‐specific service learning for exercise science students. Utilizing the American Physiological Society's “Physiology Understanding (PhUn) Week” as a launch pad, we aimed to engage exercise science majors in a field‐specific service learning project to educate local primary and secondary students about exercise science, the human body, and the scientific method. Undergraduate and graduate volunteers were tasked with developing age‐appropriate physiology lessons that would meet core curriculum standards. 3rd, 4th, 5th, and 7th grade students from a local school were brought to campus to partake in the lessons taught by the volunteers. A broad range of physiology topics were covered including all major systems and their interactions and how they are affected by exercise and diet. Volunteers spent 3‐20 hours (average ~10 hrs) developing, implementing, and teaching the lessons. The students and volunteers responded well as assessed by questionnaires returned by volunteers and teachers. The questionnaires were designed to evaluate the organization, communication, and lessons created for the students. Teachers of the students rated the program, it's relevance to curriculum and educational standards, implementation, organization, and delivery at the highest levels. Student volunteers rated their involvement as rewarding, fun, and meaningful, and all believed it was a good use of their time. Overall, this exercise science service learning project was successful and proves that educational outreach programs can be successful for all involved without prohibitive time commitments.
Using Role‐Playing Simulations to Teach Endocrine and Respiratory Physiology in Large Classes
Authors: Hull Kerry
Published: June 2021

Role‐playing simulations can help students master complex physiological processes, but may be less effective in larger classes if most students are observers instead of participants. The current study addressed this issue by evaluating the effectiveness of dividing the class into support groups for each role‐playing student. Depending on the situation, support groups provided advice verbally or via clickers. The simulations emphasized higher‐order thinking by asking students to predict how the simulation would change under different conditions. The first role‐playing exercise addressed negative feedback in the hypothalamic ‐pituitary‐target gland axis, using instrument noises to represent the hormonal output of the hypothalamus (drum), anterior pituitary (clapper), and target gland (clanger). After practicing the simulation under normal conditions, students worked with their support groups to predict how the simulation would change in response to perturbations such as an altered steady state, dysfunction of the target organ, or a tumor (an audience member playing an additional instrument). The second exercise examined the mechanics of ventilation by asking concentric circles of students to represent the chest wall/diaphragm, pleural membranes, and lungs. Students predicted how the circles would move during normal inspiration and expiration and under disease conditions (pneumothorax, emphysema, pulmonary fibrosis). Mastery of relevant concepts was examined both in the short term, by pre‐ and post‐testing, and in the long term, by examining exam performance, and student perceptions were studied using anonymous surveys. In summary, adding elements of “predict and test” and support groups to role‐playing simulations may increase their utility in larger classes.
Worming a Model Organism into Capstone Research Projects
Authors: Crum T , Sarathy J
Published: June 2021

Biochemistry/Molecular Biology majors participate in a capstone Cell Biology laboratory research course – the last course of a three part series covering gene manipulation, protein expression, and protein function. We use cell lines to study the function of proteins such as cystic fibrosis transmembrane conductance regulation (CFTR), an apical Cl‐ channel. In mammalian intestines, excess luminal bile acids affect the growth of colonic epithelial cells and increase secretion resulting in fluid loss. Students studied the effects of bile acids on the function of intestinal CFTR as it is implicated in bile acid induced diarrhea.

In addition to working with cell lines, Caenorhabditis elegans (C. elegans) was used to develop the students' understanding of the use of model organism in research. C. elegans are nematode worms that are inexpensive and easy to cultivate using equipment present at most undergraduate institutions. The Caenorhabditis Genetics Center generates and provides mutant animals. Worms have organs including intestines. Worms are transparent, making visualization of fluorescent protein fusions and organs possible in live organisms.

Students visualized CFTR homolog gene expression in live worm intestines using fluorescent transgenes (Leica DMR microscope attached to a Retiga 1300 CCD camera with Q‐Imaging software) and characterized the effects of bile salts on worm growth, intestinal morphology and luminal volume in WT and CFTR homolog mutants.

Cell lines provide an excellent reductionist model to study CFTR function. However, introducing work with C. elegans allowed students to place their work in the context of a live organism by assaying and visualizing changes in intact, functioning intestines. Students were excited to give multimedia presentations showcasing their findings and introduce this model at local and regional meetings.
Connecting Undergraduate Learning in the Life Sciences to Authentic Professional Practices Enhances Understanding and Socialization in the Discipline of Physiology
Authors: Waters Erica , Keesom Sarah , Sylvia Kristyn , Schlegel Whitney
Published: June 2021

Authentic disciplinary practices engage students with the habits of mind and ways of knowing in the discipline. A need for change in undergraduate life sciences education has been established by diverse stakeholders, with a clustering of recommendations directed towards implementing authentic learning assessment and student experiences; including but not limited to, shifting course content requirements to competency requirements (AAMC& HHMI, 2009), establishing high‐impact practices to align with expectations for learning (AAC&U, 2008) and providing authentic disciplinary experiences that reveal the process of science (AAAS Vision & Change, 2011). Collaboration and innovation in the workplace go hand‐in‐hand and the enterprise of science and communicating science is collaborative. Writing in the discipline facilitates understanding and socialization in the discipline. This study presents evidence of student learning in a senior capstone course where students learn physiology in semester teams within the context of patient cases and engage in collaborative writing, inquiry, presentation, and peer review with individual reflection on the learning process and peer evaluation. In a 2‐year study, collaboratively written case reports and research reports paralleled semester improvement in individual and team exam performance. Student‐driven team inquiry project posters ranked consistent with team writing in the discipline. Members of high performing and most improved writing teams were able to articulate collaborative writing strategies, value the collaborative writing process, and demonstrated disciplinary ways of knowing in their final writing products.
Rapid Prototyping of a Skeletal Muscle ‐ An Engineering Application in an Anatomy and Physiology Course
Authors: Stecher Nadine , Chomyszak Stephen
Published: June 2021

The Wentworth Institute of Technology (WIT) is an undergraduate institution with a focus on teaching technical design and engineering. Biomedical Engineering students are required to complete the Anatomy & Physiology course sequence. Recently, the teaching effort at WIT is moving towards an externally‐collaborative, project‐based, interdisciplinary curriculum for learning – experiential learning with the goal of career success. As part of the Anatomy & Physiology I course, we developed an interdisciplinary project that concentrates on rapid prototyping, the fabrication of a 3D scale model of an object with the help of computer software. This technique has become increasingly popular in the biomedical engineering industry. Students were given the opportunity to become familiar with the rapid prototyping method and apply it to a biological concept. Students designed and printed a 3D representation of a skeletal muscle. The project was accomplished in groups of 3‐4 students and was co‐taught by instructors of the Departments of Sciences and Mechanical Engineering & Technology. The summative assessment included an oral and written presentation of the project outcome. The perception of learning gains was measured with an anonymous post‐project student survey. The act of integrating tactile muscular facsimiles onto a scaled skeleton provided the students with a better understanding of the reasons why muscles are shaped the way they are and how they work together to manipulate the human skeleton. In addition, the students were able to implement the concepts of the human musculoskeletal system in one of the state‐of‐the‐art design and manufacturing methods in Engineering.
Implementing the use of Service‐Learning in an Undergraduate Human Physiology Course at Elon University
Authors: Uno Jennifer
Published: June 2021

Active learning is a method that engages students in academic content through reading, writing and discussion that promotes analysis and synthesis of course material. Service learning (SL) connects academic content to community‐based projects. Research on service learning pedagogy documents the many benefits that students receive from community activities and recent work supports the idea that service learning can increase the students' learning of course material. The goal of this study was to determine if incorporating SL activities in a human physiology course will augment student learning as well as increase public service and civic participation among undergraduate science majors. Elon Undergraduates enrolled in the SL course developed inquiry‐based interactive projects to bring hands‐on learning to 6th grade students at Western Middle School in Elon, NC. It is hypothesized that the development of these projects will reinforce complex topics covered in a human physiology course and enhance student communication skills that will serve them as pre‐health professional students. In addition the course will simulate 6th grader interest in science and foster community relations between Elon University and the greater Burlington community. Feedback from student evaluations indicate that 100% of enrolled students thought the community outreach was a positive experience with about 85% of the class being able to relate their classroom experience to their future goals in some capacity. 70% of the class indicated they would want to continue some sort of civic engagement in the future. Early observation and feedback indicates that SL activities do support active learning practices in a human physiology course.
Community event promotes active engagement in science
Authors: Brooks Kelsi , Paquin Zachary , Johnson Kathryn
Published: June 2021

A small liberal arts college in the midwest collaborated with local partners to develop a community event, Family Discovery Night, with the objective of exciting and engaging the public about the implications, importance, and value of science through active learning. More than 1,000 community members attended this one‐night annual event held on the college campus in the fall. The aim of the current study was to evaluate how the visitors perceived the event and how the event engaged scientific thinking with their friends and families. Children (n=57) were interviewed about their reactions on how the event influenced their excitement to engage with science, and they were given disposable cameras (n=18) to document their experience at the event. Adults (n=118) completed surveys that assessed demographics, the effectiveness of promotional materials, improvements for the event, and the value of the event to families. The interviews revealed children's positive attitudes towards science after participating in the event's hand‐on activities. The photos taken by the children document specific themes, including activities experienced for the first time and the lively community atmosphere. The surveys indicated that families in the area value the community event and the connection between the college and community. This assessment demonstrated the impact of engaging in active science learning and the benefit of connections between the community, the college, and local partners that creates awareness, excitement, and understanding of science in the community.
Morphological Analysis of the Saphenous Nerve in the Dog
Authors: Doyle Tristan , Lopez Mandi , McNulty Margaret
Published: June 2021

Owners spend millions of US dollars to alleviate pain from stifle osteoarthritis (OA) pain in pet dogs each year. Neurectomy of the saphenous nerve has been shown to effectively alleviate symptoms of knee OA in humans. In order to translate this therapy to the dog, saphenous nerve branches and innervation must be identified. The hind limbs of seven fixed canine cadavers, male and female, were dissected to trace the course of the saphenous nerve. After skin removal, the femoral nerve was traced distally to the branching of the saphenous nerve at the proximal border of the femoral triangle. The saphenous nerve was then traced distally between the caudal head of the sartorius muscle and the cranial head of the gracilis muscle to the level of the stifle (knee). The femoral artery was traced distally to the branch of the saphenous artery, which was then traced to the level of the stifle. The saphenous nerve was identified in all limbs and remained superficial until the level of the medial femoral epicondyle, in close proximity to the saphenous artery. A consistent branch left the saphenous nerve and coursed cranially to the stifle, where it appeared to innervate the medial aspect of the stifle joint capsule. In addition, other minor branches supply surrounding musculature were observed and documented. This study determined that the saphenous n. appears to provide substantial innervation to the medial side of the stifle joint in the dog. Future work would need to be done to confirm the joint structures these branches innervate and whether ablation would result in OA symptom relief. Financial support provided by NIH Bridges to the Baccalaureate Program.
Seriated CT‐Scan of a Naturalized Crocodile in the Frontal Plane
Authors: LE FLOCH‐PRIGENT PATRICE , VERDEILLE STEPHANE , GILLOT JEAN‐BERNARD
Published: June 2021

A 98 cm long, naturalized crocodile had been CT‐scanned all along his length when laid on the radiological table. The apparatus was a 128 detector rows 's, Siemens somatom edge CT‐scan. Near one thousand (1000) frontal cross‐sections were obtained. They revealed the removal of all the skeleton inside the skin except the head where the osseous data could be detailed. The remnant body was filled with a common material thus the shape of the neck, trunk, tail and of the four limbs could be appreciated. Thirteen (13) external views had been reconstructed from the cross‐sections and were of good morphological value. The CT‐scan has proved to be an unvaluable method in every gross‐morphological anatomical study.
Evaluation of Toxicological Effects of Tartrazine Food Additive on histomorphic architecture of liver of Wistar Rats
Authors: Ugochukwu Chioma , IHENTUGE CHURCHILL , Okechukwu Hope
Published: June 2021

Tartrazine is an artificial orange‐colored azo dye, it is a water soluble powder widely used in food products, drugs and cosmetics. Twenty four adult Wistar rats, weighing between 150‐200g, were used in the study to evaluate the toxicological effects of Tartrazine food additive on histomorphology of liver of wistar rats. They were divided into four groups of six animals each designated as groups A, B, C and D. Group A served as Control group and was fed with diet and tap water only during the experimental period of 30days. Groups B, C and D were fed with standard diet and given a solution of Tartrazine at a daily dose of 7.5mg/kgbw, 10mg/kgbw and 12.5mg/kgbw respectively for the same duration. At the end of the experimental period, rats were sacrificed using Chloroform. The liver was dissected out from each group, weighed and processed for histological study. Results showed a decrease in mean body weight gain of the experimental rats as the dose of Tartrazine increases (12% increase (Group B), 6% increase (Group C) and 3% increase (Group D) when compared to the control group of 30%). The relative weight of liver of the experimental groups also increase with increase in the dose of tartrazine (2.32±0.3, 2.50±0.17 and 2.80±0.20 for groups B, C and D respectively). The increase was significant in group D when compared with the control group (p<0.05). Histologically, the liver architecture in group D showed mild inflammation, cellular infiltrations and moderate fatty changes while that of groups A, B and C appear normal. This showed that tartrazine, a food additive is capable of causing liver damage at a high concentration or after a chronic consumption