bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bio‐inspired micropattern modulates stem cell fate and directs well‐ordered tubular tissue formation
Authors: Liu Xiaohua 
Published: June 2021

Many tissues in the body possess highly‐organized microstructures that are a prerequisite for their physiological functions. However, regeneration of the tissues with well‐ordered microstructures has long been a challenge due to unprecedented technology difficulties. Here, we report a unique maskless micropatterning technology to create bio‐inspired nanofibrous 3D matrices with highly‐organized microstructure for tubular tissue regeneration. Our micropatterning method is a laser‐guided, non‐contact, high‐precision, flexible computer programming of machining process that creates highly‐ordered tubules (2–5 μm) in the bio‐inspired 3D matrix. The tubular architecture presents pivotal biophysical cues to control dental pulp stem cell alignment, migration, polarization, and differentiation. More importantly, when using this hierarchical matrix as a template, we successfully regenerated functional tubular dentin (the main component of a tooth) in vivo. Our bio‐inspired micropattern approach represents a powerful avenue not only for the exploration of a range of fundamental biological questions, but also for the regeneration of functional tissues with well‐organized structures.Support or Funding InformationThis research is supported by NIH/NIDCR R01DE024979.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Glycemic Index Determination of Plant‐ and Whey‐Based Protein Nutritional Shakes
Authors: Glynn Erin L. , Alamdari Nima , Wilson Michael , Ezatagha Adish , Jenkins Alexandra L. , Sharafi Mastaneh 
Published: June 2021

BackgroundThe glycemic index (GI) is used to classify carbohydrate‐containing foods and products according to their effect on postprandial blood glucose responses. Low GI products release carbohydrates more slowly and elicit a lower glycemic response than higher GI products. Accordingly, low GI diets may help with weight and general health maintenance. The purpose of this study was to determine and compare the glycemic index of 4 flavors of plant‐based protein shakes and 4 flavors of whey+plant‐based protein shakes (Shakeology®, Beachbody, LLC).MethodsGI was determined using the standard ISO method (ISO 26642:2010). Ten subjects (7 male, 3 female) aged 44 ± 13 with a body mass index of 26.4 ± 2.3 kg/m2 participated in this open‐label, randomized, crossover study. Subjects consumed the designated test shakes or dextrose control in a randomized order (all 25 g available carbohydrate). Blood samples were collected at time −5 and 0 (baseline) and at 15, 30, 45, 60, 90, and 120 minutes after product consumption. GI was calculated by expressing each subject's glucose incremental area under the curve (AUC) for the test shake as a percentage of the same subject's mean response to the dextrose control tests. GI values were expressed using the glucose scale where dextrose = 100.ResultsThe GI values of the tested plant‐based shakes were: Vegan Chocolate and Café Latte flavors = 36 ± 5, Vegan Strawberry and Vanilla flavors = 37 ± 6. The GI values of the tested whey+plant‐based shakes were: Chocolate and Café Latte flavors = 33 ± 5, and Strawberry and Vanilla flavors = 29 ± 5. All of the 8 shakes tested were classified as low GI based on standard classification of low GI ≤ 55, medium GI 56 – 69, and high GI greater than 70. In addition, blood glucose levels dropped 8% below baseline following dextrose ingestion, but were within 1% of baseline for all tested shakes.ConclusionAll varieties of Shakeology evaluated tested as low glycemic index. GI values were not different between the plant‐based protein and the whey+plant‐based protein varieties.Support or Funding InformationThis study was funded by Beachbody, LLC. Testing was independently conducted by GI Labs, Inc., Toronto, ON, Canada.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
An Evolutionary Conserved DNA Replication Stress Response in Planarian
Authors: Shamoon Ushna , Tirgar Reyhaneh , Akpati Lois , Sawyer Nathaniel , Nam Edward 
Published: June 2021

S. mediterranea is a planarian with extensive regenerative ability which requires substantial cell division. Adult stem cells (SCs) divide many times over an organism's lifespan to renew tissues. The reduced capacity of adult SCs to regenerate old and damaged tissue results in aging. However, DNA replication stress occurs every cell division and must be resolved. From yeast to man, an evolutionary conserved DNA replication stress response (RSR) is essential for life. The RSR is a signal transduction pathway regulated by Ataxia‐telangiectasia and Rad3‐Related kinase (ATR) and Checkpoint 1 kinase (CHK1) to respond to replication stress. However, the RSR has not been established in planarian nor do we know if it functions in regeneration. We hypothesize that the RSR may be essential for regeneration. Preliminary results show reduced regenerative ability in the presence of hydroxyurea (HU), a replication stress inducing agent. However, low concentrations (2mM) did not attenuate regeneration, indicating that the RSR may be present and able to overcome replication stress. To test this, we treated amputated tails with HU, ATR inhibitor (ATRi), and a combination of both. In 2mM HU, tails regenerated similarly to control. We observed only a one day delay in regeneration with ATRi alone. However, ATRi and 2mM HU in combination prevented planarian regeneration completely. This synergistic effect suggests that ATR is significant in the response to replication stress during regeneration. To obtain genetic evidence, we are in the process of knocking down ATR as well as other RSR genes like CHK1, WRN, etc. Further determining the importance of RSR genes in planarian will elucidate the conserved components and allow us to understand how the RSR contributes to the incredible regenerative abilities in planarian.Support or Funding InformationThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Characterization of A Novel S‐adenosylmethionine‐dependent Methylase by Electron Paramagnetic Resonance and Mössbauer Spectroscopies
Authors: Radle Matthew , LaMattina Joesph , Booker Squire 
Published: June 2021

Radical S‐adenosyl‐L‐methionine dependent methylases are divided into four classes (A–D) with only A through C being extensively characterized in vitro. Class D methylases separate themselves by purportedly utilizing methylenetetrahydrofolate in their catalysis‐. The gene product from Methanocaldococcus jannaschii, MJ0619, is the pioneer member of this class and is hypothesized to install methyl groups into C7 and C9 of methanopterin, a key coenzyme for C1 metabolism in methanogeneic and methylotrophic bacteria. By extracting folates from E. coli transformed with a plasmid containing the MJ0619 gene, Allen, et.al. were able to detect and characterize methylated substrates and determine that 7‐methylpterin and 6‐ethyl‐7‐methylpterin were produced in vivo. Feeding studies in which E. coli were grown in media containing C2H3‐ methionine or C2H3‐acetate suggested that MJ0619, unlike members of classes A‐C, does not use SAM, but rather methylenetetrahydrofolate as the methyl donor. Excitingly, MJ0619 harbors a second CX3CX2C motif hypothesized to ligate an additional [4Fe‐4S] cluster and when the middle cysteine of this motif is changed to an alanine only 7‐methylpterin is detected. Although it is suggested that the N‐terminal Fe/S cluster is involved in C9 methylation there is little in vitro evidence to support this function and no spectroscopic characterization to identify it as a [4Fe‐4S] cluster. Herein, we report the heterologous expression and isolation of MJ0619, a member of a class D methylases, and employ Mössbauer and electron paramagnetic resonance spectroscopies to characterize its Fe/S cluster(s) of MJ0619.Support or Funding InformationHoward Hughes Medical InstituteThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Curli Proteins CsgE and CsgF Inhibit the Aggregation of Human Islet Amyloid Polypeptide
Authors: Khan Neelam , Arlantico Megan , Feliciano Elizabeth , Nguyen Hannah , Jayasinghe Sajith 
Published: June 2021

Curli, a type of proteinaceous cell surface filament, found on enteric bacteria such as E. Coli and Salmonella, are thought to play an important role in host cell adhesion and invasion. The assembly of CsgA, the major structural protein of Curli, into fibers is aided by three non‐structural proteins, CsgE, CsgF, and CsgG. CsgE and CsgF are thought to be periplasmic chaperone proteins that play a vital role in the assembly of Curli fibers. It has been shown that CsgE is able to prevent the aggregation of CsgA into Curli fibers. We determined the ability of CsgE and CsgF to inhibit the aggregation of human Islet Amyloid Polypeptide (hIAPP), an amyloidogenic protein unrelated to Curli formation. We monitored the aggregation of hIAPP, using the fluorescent dye ThT, in the absence and presence of CsgE and CsgF. An increase in ThT fluorescence emission intensity is routinely used to detect the aggregation of amyloidogenic polypeptides. In the absence of CsgE or CsgF we observe a greater than 5‐fold increase in fluorescence intensity when freshly dissolved hIAPP is monitored in the presence of ThT. Such an increase in intensity is typically taken to indicate the aggregation of hIAPP. In the presence of CsgE and CsgF no significant increase in ThT intensity is observed suggesting that both CsgE and CsgF prevented the aggregation of hIAPP.Support or Funding Information1. This work is supported by NIH grant 1R15GM123430‐01This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Induction of Neoplastic Transformation, AP‐1 Signaling, PDCD4 signaling, and DNA Damage by Copper Oxide Nanoparticles Involves ROS‐Mediated MAPK Pathways in JB6 Cells.
Authors: Barber Tabatha L. , Aldinger Joni , Tenney Allyson , Leonard Stephen , Morris Anna , Ding Min 
Published: June 2021

Occupational exposures to copper dusts or fumes have beenreported to be harmful to human health, with possible risk of cancer amongcopper smelting workers. Copper (II)oxide (CuO) nanoparticles have not, to our knowledge, been extensively examinedfor potential carcinogenic or genotoxic effects. To investigate the mechanismsof CuO‐induced pathogenesis, the effect of CuO on AP‐1‐MAPKs and ROS generation were investigated. The results indicated that CuO caused a 2‐fold increase in AP‐1 activity in JB6 cells. The induction of AP‐1 activity in cultured cell lines was time and dose‐dependent. The signal transduction pathways for AP‐1 activation were also investigated. Western Blotanalysis demonstrate that CuO nanoparticles stimulate phosphorylation of p38MAPK and ERKs. CuO also generated ROS when incubated with the cells as measured by electron spin resonance (ESR). Nano‐sized CuO generated more ROS than the fine sized particles when incubated with the cells. COMET assay suggests that exposure of the cells to CuO resulted in DNA damage. Cells pre‐treated with ROS inhibitors sodium formate and Polyvinylpyridine‐N‐Oxide (PVPNO) before exposure to CuO nanoparticles demonstrate a significant reduction in p‐38 and ERK activity, suggesting the H2O2 may have a role in the ROS mechanism. Soft agar transformation assays demonstrated that there is a significant increase in colony formation in JB6/AP‐1 cells treated with CuO nanoparticles as compared to the control, indicative of neoplastictransformation. Unraveling the complex mechanisms associated with these events may provide insights into the initiation and progression of CuO‐induced pathogenesis.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Aggregated CsgA Does Not Form In‐Register Parallel Structures
Authors: Basham Michael , Guevarra Culbert , Meza‐Barajas Osmar , Godfrey Gabriel , Jayasinghe Sajith 
Published: June 2021

Curli are hair‐like fibers used by the bacteria for adhesion and invasion, implicating them in the pathogenesis of bacterial disease. The main protein component of Curli is CsgA, and the main focus of our work is to characterize the structure of oligomerized CsgA. We expressed six C‐terminally histidine tagged single cysteine mutants of CsgA and used circular dichroism (CD) spectroscopy and pyrene fluorescence spectroscopic techniques to determine structural changes that occur during protein aggregation. CD spectra obtained immediately after addition of CsgA to buffer exhibit minima at approximately 200 nm, characteristic of a random coil conformation, indicating that CsgA is predominantly unstructured in solution. In contrast, CD spectra obtained after incubating CsgA in buffer exhibit minima at approximately 218 nm. These spectra are characteristic of β‐sheet conformation, indicating that CsgA undergoes a random coil to β‐sheet conformational change upon incubation. We also observed an increase in Thioflavin T fluorescence intensity upon incubation of CsgA in buffer indicating the formation of protein aggregates. Fluorescence spectra obtained of CsgA labeled at positions 24, 41, and 55 with pyrene did not contain a peak at 475 nm due to pyrene excimer formation, indicating that aggregated proteins are not arranged in an in‐register parallel fashion.Support or Funding Information1. This work is supported by NIH grant 1R15GM123430‐01This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Arsenic‐Induced Perturbations in Cholinergic System and Energy Metabolism of Rat Brain: Ameliorative effect of Vitamin‐E
Authors: Chinthirla BD , Konduru KK , Kozlova EV , Curras‐Collazo MC 
Published: June 2021

Chronic exposure to inorganic arsenic compounds may lead to peripheral and central neurotoxicity. The aim of this study was to examine the impact of Arsenic (As) exposure on cholinergic and bioenergetic systems in three brain regions: cerebral cortex, cerebellum and hippocampus. Adult male Albino rats at 3 months of age were exposed to low (1.5 mg/kg body weight) and high dose As (3 mg/kg body weight) through intraperitoneal injection daily for a period of 3 weeks. A separate batch of rats were given α‐tocopherol (5mg/kg body weight) for a period of one week immediately after the low and high dose As exposure. The acetylcholinesterase (AChE) activity and acetylcholine (ACh) content in synaptosomal fractions and Mg2+‐ATPase and Na+/K+‐ATPase activities in mitochondrial fractions. We found that As treatment had decreased AChE, Mg2+‐ATPase and Na+/K+‐ATPase activities and increased in ACh content when compared to control (sham‐injected). The high dose As treated rats showed significantly decreased AChE, Mg2+‐ATPase and Na+/K+‐ATPase activities and increased ACh content compared to low dose As treated rats. The maximal alteration of these enzymes was observed in hippocampus among the three brain regions. Whereas, the rats supplemented with α‐tocopherol (along with As) showed a reversal effect with slight increase in enzyme activities and decrease in ACh content in a dose dependent manner. In addition to this, As exposure decreased mean body weights in a dose dependent manner. This study demonstrates that exposure to As provoked neurochemical and metabolic disruption by inducing alterations in enzymes of cholinergic system and energy metabolism. Moreover, Vitamin‐E treatment may have partial ameliorative effects on these disturbances caused by As toxicity.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Determining Invertase Enzyme Activity Using Isothermal Titration Calorimetry
Authors: Chan Dindi , Anderson Jeremy , Kenealey Jason 
Published: June 2021

Invertase catalyzes the hydrolysis of sucrose producing fructose and glucose. Invertase is widely used in the food industry because it possesses a lower crystallinity than sucrose at higher concentrations and is sweeter than sucrose. Invertase enzyme activity is typically measured using an endpoint coupled‐secondary reaction. The glucose produced by the invertase‐catalyzed reaction reacts with 4‐hydroxybenzoic acid hydrazide to produce yellow anions that can then be measured spectrophotometrically. Contrary to the standard method for measuring invertase activity, single injection isothermal titration calorimetry (ITC) directly measures heat generated by invertase continuously. ITC provides rapid and efficient measurement for enzyme activity. However, recent studies have shown that the single injection ITC measurements cannot separate km and kcat because the enzyme does not reach saturation. We recently demonstrated that single injection ITC can be used to measure the stability of invertase activity. Here we further characterize the relationship between the peak invertase activity and the peak heat‐rate. Additionally, previous ITC measurements of invertase activity have demonstrated that there is a delay in peak invertase activity. We elucidate the dependence of this delay in activity on the sucrose concentration. Single injection ITC is uniquely positioned to provide insight into the mechanistic action of invertase that cannot be determined using coupled reactions.Support or Funding InformationBuild DairyBYU MEG GrantThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Invasion and Inhibition in Cell Embryonic Migration
Authors: Kulesa Paul , McLennan Rebecca , McKinney M Cathy , Teddy Jessica M. , Morrison Jason A , Kasemeier‐Kulesa Jennifer C , Giniunaite Rasa , Robinson Martin , Baker Ruth , Maini Philip 
Published: June 2021

The embryonic neural crest offers a unique model system in which to study cell migration mechanisms in vivo during development and disease. The neural crest is a highly invasive, multipotent cell population that displays a regulated spatio‐temporal migratory pattern in the vertebrate embryo. Importantly, several aggressive tumor types, including melanoma and neuroblastoma, originate from neural crest‐derived cells. This has led to the hypothesis that neural crest‐related malignancies may be intrinsically predisposed to increased metastatic potential due to the inherent invasive abilities of the neural crest. I will discuss our recent findings of novel neural crest invasion and inhibitory signals that sculpt the embryonic cell migration pattern and provide insight into limiting metastatic behaviors.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Ube2v1, a ubiquitin‐conjugating enzyme variant, is an essential component for the ubiquitination of MEKK1 in FGF2‐mediated signaling in endothelial cells
Authors: Yoo Yung Joon , Elangovan Muthumumar , Jin Suk Won 
Published: June 2021

Ubiquitin can be covalently conjugated to target proteins to provide a critical signal in diverse cellular processes. Given that ubiquitination is catalyzed by an E1‐E2‐E3 cascade of enzymes but the actual formation of peptide bond mostly occurs at the active site of E2, we decided to screen the mRNA level of E2s in the endothelial cells, intending to find the role of ubiquitination in angiogenesis. Based on our initial microarray data identified 33 E2s in human and its 25 paralogs in zebrafish, we analyzed the expression level of 25 E2s in endothelial cells of zebrafish embryos and found that Ube2v1, a ubiquitin‐conjugating enzyme variant, is the most highly expressed E2. The knockdown of Ube2v1 using siRNA significantly inhibited the proliferation and migration of human umbilical vein endothelial cells (HUVECs). It was also found that Ube2v1 was an essential component for FGF2‐mediated activation signaling by the ubiquitination of MEKK1 with K63‐linked ubiquitin chains. Interestingly, Ube2v1 was not involved in the VEGF‐A induced signaling in HUVECs. Although Ube2N is a canonical partner of Ube2v1 for K63‐linked ubiquitination, siRNA‐mediated knockdown of Ube2N had no effect, implying an alternative E2 partner for Ube2v1 for the ubiquitination of MEKK1.Support or Funding InformationThis work was supported by the GIST Resach Institute (GRI).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
More Efficient Breakdown of PET Plastic by Modifying the PETase Enzyme
Authors: Duplan Amanda , Hall Bonnie L. 
Published: June 2021

Overproduction and improper disposal methods have caused the world's oceans and ecosystems to be polluted with plastic waste. Polyethylene terephthalate (PET) is a thermoplastic polyester resin widely used in plastic products. PET plastic contains a high ratio of aromatic components that are poorly reactive and difficult to degrade, so PET remains in the environment for an extensive time. In 2016, the novel bacterium Ideonella sakaiensis was discovered to be capable of using PET as a carbon source for growth. The enzyme PETase was isolated from the bacterium and found to break down PET plastic at a slow rate. Our goal is to modify the PETase enzyme to hydrolyze PET plastic with a higher efficiency. The over‐expression and purification of the PETase protein has been optimized. High performance liquid chromatography and nuclear magnetic resonance assays are being used to measure the rate and efficiency of PET breakdown. PETase with various amino acid substitutions has been generated, with the goal of improving enzyme activity under commercially relevant conditions. An optimized PETase enzyme capable of degrading these plastics efficiently on a large scale could be the first step to repairing our polluted ecosystems.Support or Funding InformationThis work was supported in part by the FUTURE program at the University of Iowa Carver College of Medicine.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.