bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of immune cells and proinflammatory substances as biocompatibility markers of dental sealers
Authors: NAKAGOSHI‐CEPEDA AKEMI argelia , SOLIS‐SOTO JUAN MANUEL 
Published: June 2021

A variety of studies have demonstrated that root canal sealers induce mild to severe inflammatory reactions. Several factors participate in this immune response. Analysis of these factors can be indicative of biocompatibility.ObjectiveIn this study immune cells and proinflammatory chemokines and cytokines are analyzed in response to dental sealers of different composition.MethodsAfter Apexit (calcium hydroxide based), Portland or MTA were implanted in the dorsal dermis of BALB/c mice, histopathological and immunocytochemical studies were performed to analyze the presence of a) Macrophages and CD8 lymphocytes, b) Cells producing proinflammatory cytokines (IL‐1beta, IL‐6, and TNF‐alpha), and c) Cells producing proinflammatory chemokines (CCL5 and CCL20).ResultsAll treated materials produced a mild inflammatory reaction. Apexit was the most biocompatible, with results similar to controls, except for 12 hours post‐implantation, when significative more IL‐6 and CCL20 immunoreactive cells were observed (p<0.05). Macrophages, CCL20 and IL‐6 were in higher amounts in mice implanted with MTA in comparison than Portland (p<0.05).ConclusionsThe calcium hydroxide based dental sealer showed better in situ biocompatibility than calcium silicate oxide sealers.
Functional studies of the Med25 Mediator subunit in Arabidopsis thaliana
Authors: Björklund Stefan , Elfving Nils , Davoine Celine 
Published: June 2021

We recently purified the Mediator complex from Arabidospsis thaliana (At) (B ?ckstr ?m et al., 2007). This is so far the only example of Mediator identified in plants. We could show that the AtMed25 subunit is identical to PFT1 (PHYTOCHROME AND FLOWERING TIME 1). PFT1 was originally identified as a nuclear protein that acts in a phyB pathway and induces flowering in response to suboptimal light conditions (Cerdán and Chory, 2003). In mammalian cells, Med25 is identified as the Mediator subunit that functions as target for the VP16 transcriptional activation domain ([Mittler et al., 2003] and [Yang et al., 2004]). The VP16 was mapped to interact with a region between amino acids 402‐543 of the mammalian Med25 and this domain is conserved in AtMed25. We have used the corresponding region of AtMed25 in yeast 2‐hybrid screening assays to identify potential plant‐specific transcriptional activators involved induction of flowering at suboptimal light conditions by interaction with AtMed25. We have so far identified three transcription factors that operate through AtMed25 and the results indicate that Med25 might function in integration of different signaling pathways that control flowering.This work was supported by grants from the Swedish Research Councils Formas and Natural and Engineering Sciences.
Characterization of ZBP1‐βactin mRNA complex
Authors: Chao Jeffrey Alan , Singer Robert 
Published: June 2021

Zipcode binding protein 1 (ZBP1) belongs to a family of highly conserved RNA‐binding proteins that have been linked to several steps in the post‐transcriptional regulation of gene expression including mRNA stability, localization and translation. This family of proteins functions during embryogenesis and is often found over‐expressed in a variety of cancers. ZBP1 was first identified by its ability to promote the localization of beta‐actin mRNA to the leading edge of chicken embryo fibroblasts through its interaction with cis‐acting elements contained within the beta‐actin mRNA.ZBP1 contains two RNA recognition motifs (RRM) followed by four hnRNP K homology (KH) domains. We have identified a fragment of ZBP1, which contains both KH3 and KH4, that binds to a 28 nucleotide region of the beta‐actin mRNA with high affinity. KH3 and KH4 function together as one domain and bind RNA as a monomer. Mutation of the amino acids that link KH3 and KH4 reduces binding affinity by greater than 100‐fold suggesting that the orientation of the RNA binding surfaces is important for RNA recognition.While ZBP1 KH34 has remained recalcitrant towards crystallization, we have recently obtained crystals of IMP2 KH34, a paralog of ZBP1 with 82% sequence identity, that diffract to 2Å resolution. A molecular replacement solution has not yet been identified, so experimental phases are being determined.
Small RNA, Big Impact: Probing miRNA pathways in living cells using single particle tracking
Authors: Pitchiaya Sethuramasundaram , Androsavich John R , Sobhy Mohamed A , Walter Nils G 
Published: June 2021

MicroRNAs (miRNAs) are short non‐coding RNAs that control the expression of an estimated 30% of all human proteins post‐transcriptionally. Mature miRNA, typically 21 base pairs long, associates with several proteins to form a miRNA Induced Silencing Complex (miRISC). This complex associates with the Un‐Translated Region (UTR) of mRNAs in a sequence specific manner and forms an active miRISC that controls protein expression. While several different mechanisms have been proposed for miRNA mediated gene repression, they are highly debated. We are investigating the mechanism of miRNA action by observing the diffusive motions of miRISC‐mRNA complexes in living cells using single particle tracking microscopy (SPTM). To this end, we microinject fluorophore labeled miRNA probes into living cultured cells. The probe can bind to multiple sites on its target mRNA which results in an inherent fluorescent amplification and significantly aids in tracking the particle. Quantitative Real Time ‐ Polymerase Chain Reactions (qRT‐PCR) were performed to estimate the level of the HMGA2 mRNA in F9 cells and preliminary tests suggests that there are ~8 mRNA molecules/cell, which is a suitable target number for our SPT experiments. SPT experiments are being performed using which we can deduce whether a specific miRISC‐mRNA complex progresses through multiple mechanisms of repression.Funded by NIGMS.
A switch from BAG1 to BAG3 during ageing triggers the enhanced use of the autophagic‐lysosomal system for the degradation of polyubiquitinated proteins
Authors: Gamerdinger Martin , Hajieva Parvana , Behl Christian 
Published: June 2021

BAG1 and BAG3 are members of the Bcl‐2‐associated athanogene (BAG) family, a conserved group of Hsp70 co‐regulators. We show that both, BAG1 and BAG3, are involved in protein quality control: whereas BAG1 regulates the removal of polyubiquitinated proteins by the proteasomal system, BAG3 acts in concert with the ubiquitin‐binding protein p62/SQSTM1 to stimulate the turnover of polyubiquitinated proteins by the autophagic‐lysosomal pathway. Interestingly, a switch from BAG1 to BAG3 occurs during ageing of human cells as well as in neurons of the aged rodent brain. Similar to the ageing models, a shift from BAG1 to BAG3 is observed in HEK cells under protein cross‐linking conditions provoked by oxidative stress. Moreover, we show that, triggered by the increased BAG3 to BAG1 ratio, aged cells use increasingly the autophagic‐lysosomal pathway for the turnover of polyubiquitinated proteins. We conclude that the BAG3‐mediated recruitment of the autophagy pathway is an important adaptation of the cellular protein quality control system to maintain protein homeostasis in the presence of an enhanced pro‐oxidant and aggregation‐prone milieu characteristic of ageing.This work was supported by grants from the Fritz und Hildegard Berg‐Stiftung
Changes in β‐secretase activity in down syndrome and aging
Authors: Webb Robin L. , Holler Christopher J. , Beckett Tina L. , Head Elizabeth , Murphy M. Paul 
Published: June 2021

BackgroundDown Syndrome (DS) or trisomy 21, leads to Alzheimer's disease (AD) pathology by 40 years of age. Chromosome 21 harbors several genes implicated in AD, including the amyloid precursor protein (APP), and one isoform of the β‐site APP cleaving enzyme (BACE2).ObjectiveOur laboratory is interested in β‐secretase and its regulation in different disease states. DS provides a unique model for evaluating changes in regulatory factors that influence the proportion of DS patients with AD.MethodsWe used a fluorometric assay developed in our lab to evaluate both BACE1 and BACE2 activity from a set of 24 DS (0.42‐62 years) and 16 control (0.45‐67 years) brains (Brodman area 9). Results andConclusionsBACE1 significantly decreased (p<0.04) with age, a finding differing from the situation seen in both AD and with normal aging in rodents and non‐human primates. Surprisingly, BACE2 was unchanged, even though the gene for BACE2 is located within the DS obligate region of chromosome 21. Finally, BACE1 and BACE2 activity levels were highly correlated in this series (r2 = 0.95), indicating that there may be a higher degree of shared regulation than previously believed. Additional studies will examine the relationship between amyloid pathology and enzymatic activity. Insight gathered from these studies will help understand the nature of the shared pathology in both diseases. Supported by NIH NS058382.
Rocking Motion of the Equatorial Domains of a Group II Chaperonin between Two Biochemical States Revealed by Single‐Particle Cryo‐EM at Near‐atomic and Subnanometer Resolutions
Authors: Zhang Junjie , Baker Matthew , Schroeder Gunnar , Douglas Nick , Jakana Joanita , Fu Caroline , Levitt Michael , Ludtke Steven , Frydman Judith , Chiu Wah 
Published: June 2021

Chaperonins consist of two rings which are stacked back‐to‐back, forming folding cavities where substrates are encapsulated. The closure of the chaperonin cavity is triggered by ATP binding or hydrolysis. We report four single‐particle cryo‐EM structures of both wildtype and mutant Mm‐cpn, an Archaeal chaperonin in the nucleotide free and nucleotide bound states. The 4.3‐4.8Å resolution maps of the Mm‐cpn closed, nucleotide‐bound state, clearly show pitches of α‐helices and separation of β‐strands. More than 56% non‐small sidechain densities are visible in the 4.3Å resolution map of the wildtype Mm‐cpn. Protein backbones are modeled for both of the closed conformations. Models are built with geometry‐constrained flexible fitting to the 8‐10Å maps of the nucleotide free Mm‐cpn which exhibits an open conformation. The open and closed structures reveal a rocking motion in the equatorial domain of all subunits which results in different molecular contacts between the two rings in these two states. We observe a ~40° tilting of the region containing the N and C termini, as mm‐cpn switches from the closed to open state. This swinging movement of the N and C termini induced by the nucleotide hydrolysis may suggest their role in the substrate folding and/or release.Research is supported by NIH Nanomedicine Roadmap grant (PN2EY016525)
Molecular Basis of D‐AKAP2 Binding to PKA Regulatory Subunits
Authors: Sarma Ganapathy , Kinderman Francis , Kim Choel , von Daake Sventja , Taylor Susan 
Published: June 2021

cAMP‐dependent protein kinase (PKA) regulates a variety of biological activities by phosphorylating a broad range of target proteins. Spatial and temporal specificity of PKA activity is, in turn, achieved by a family of scaffolding proteins called as the A‐kinase anchoring proteins (AKAPs). One of these, dual‐specific AKAP 2 (D‐AKAP2) binds to both the Regulatory (R) isoforms (RI and RII) of PKA. Specifically, the dimerization and docking (D/D) domain at the N‐terminus of the R subunits forms a four‐helix bundle that provides an interface for AKAP binding.In order to understand the molecular basis of D‐AKAP2 binding to the RIα subunit and understand the molecular determinants that make D‐AKAP2 dual‐specific, we have solved the structures of the RIα D/D domain with and without the D‐AKAP2 peptide. The structure of the apo crystal form was solved using the anomalous signal from inherently present sulfur atoms. Together with the existing peptide array data and the RIIα D/D structure, the present structures reveal atomic‐level information on the dual‐specific nature of D‐AKAP2. The structures also provide insights into the role of a pair of highly conserved disulfides that might function as a redox sensor in cardiac myocytes. This work was supported by an American Heart Association Postdoctoral Fellowship to G.N.S, NIH grant to DK54441 to S.T and the Howard Hughes Medical Institute.
Effect of pentachlorophenol on MAP kinases in human natural killer cells
Authors: Whalen Margaret M 
Published: June 2021

Pentachlorophenol (PCP) is an organochlorine compound that has been used as an insecticide and a fungicide. PCP use has been restricted in the USA, it is mainly used now as a wood preservative for power‐line poles and fence poles. PCP has been detected in human tissues through inhalation and consumption of contaminated food and water. Human natural killer (NK) lymphocytes play a central role in immune defense against viral infection and tumor development by killing (lysing) virally infected and tumor cells. The lytic function of NK cells depends in part upon the activation of mitogen activated protein kinases (MAPK). In previous studies we have shown that exposure to 10‐0.5µM PCP decreases the lytic function of NK cells. In this study we evaluated the effect of these same concentrations of PCP on the phosphorylation state and total levels of p44/42, p38, and JNK ,MAPKs. Preliminary studies indicate that PCP exposure is able to increase the phosphorylation (activation) of MAPKs. This PCP‐induced phosphorylation of MAPKs may leave them unavailable for activation by virally infected or tumor target cells and thus contribute to the observed decreases in lytic function seen in NK cells exposed to PCP.Supported by NIH grant S06 GM008092‐33.
Plum polyphenolics decrease oxidative stress and inflammation in vascular endothelial cells
Authors: Townsley Emily D. , Noratto Giuliana , Angel Gabriela , Del Follo Armando , Byrne David , Mertens‐Talcott Susanne 
Published: June 2021

Previous studies have demonstrated that plums are rich in antioxidant polyphenolics which may have anti‐inflammatory effects. In this study we determined the anti‐oxidant and anti‐inflammatory effects of polyphenolics extracted from ″Black Splendor″ (BS), a commercial variety of plum (Prunus salicina). BS concentrations of up to 10 mg gallic acid equiv./L did not significantly alter cell proliferation and therefore were selected for the determination of antioxidant and anti‐inflammatory effects in human umbilical vein endothelial cells (HUVEC). Reactive oxygen species (ROS) were induced with 10mM glucose for 30 min at 37°C and BS (≥2 mg/L) decreased the induced oxidative stress by up to 70% upon treatment . Treatment of HUVEC cells with 10mM glucose significantly increased messenger‐RNA expression of inflammation biomarkers IL‐6, IL‐8, and NF‐κB. An increase in transcription factor NF‐κB up‐regulates other pro‐inflammatory cytokines leading to increased vascular inflammation. Upon treatment with BS (4 mg/L), IL‐6, IL‐8, and NF‐κB were decreased by 4.4, 7.4, and 3.1 fold, respectively. This data suggests that antioxidant polyphenolics found in plum extracts help control inflammation and inhibit oxidative stress in human umbilical vein endothelial cells.Grant Funding SourceTexas A&M University Vegetable and Fruit Improvment Center
Trans‐10, cis‐12 conjugated linoleic acid (CLA)‐mediated inflammatory signaling: Essential role of human adipocytes in initiating cross‐talk with preadipocytes
Authors: Martinez Kristina Brooke , Chung Soonkyu , LaPoint Kathleen , Kennedy Arion , Walker‐West Tiffany , McIntosh Michael 
Published: June 2021

We have previously shown that both lipopolysaccharide (LPS) and CLA, a popular weight loss supplement, activate inflammatory signaling that promote insulin resistance in primary cultures of human (pre)adipocytes. Because our published data demonstrated that preadipocytes were the primary instigators of inflammatory signaling in LPS‐treated cultures, we hypothesized that they played the same role in CLA‐mediated inflammation. To test this hypothesis, we employed two experimental models; Model 1‐ a Co‐Culture Insert Model in which inserts containing ~50% adipocytes (AD50) or ~100% preadipocytes (AD0) were suspended over wells containing AD50 or AD0 cultures, and Model 2‐ a Conditioned Media (CM) Model in which naïve AD0 and AD50 cultures were treated with CM from CLA‐treated AD50 or AD0 cultures. In Model 1, CLA‐induced interleukin (IL)‐8 and IL‐1β mRNA levels were highest in AD50 cultures when co‐cultured with AD0 inserts, whereas no increase in these genes were detected in AD0 cultures. In Model 2, IL‐8 and monocyte chemoattractant protein (MCP)‐1 mRNA levels were increased in cultures treated with CM from CLA‐treated AD50, but not AD0, cultures. These data suggest that, in contrast to LPS, CLA instigates release of inflammatory signals from adipocytes that subsequently activate adjacent preadipocytes in primary cultures of human (pre)adipocytes. Supported by NIH‐NIDDK/ODS 2R01‐DK063070.Grant Funding SourceNIH‐NIDDK/ODS 2R01‐DK063070 and NCARS 06771
Unlocking the Archives: Genomic Analysis of Formalin‐Fixed Paraffin Embedded Tissue
Authors: Monzon Federico Alberto , Alvarez Karla , Lyons‐Weiler Maureen A , Kash Shera , Kim Hyun‐Jung , Hagenkord Jill M 
Published: June 2021

BackgroundVirtual karyotypes derived from SNP microarrays can be performed on formalin‐fixed paraffin embedded (FFPE) tissue samples.Methods284 archival FFPE human tissue samples (tumor and normal) were processed to obtain virtual karyotypes with Affymetrix 10K 2.0 or 250K Nsp SNP microarrays. Tissue was macro‐dissected from 10µm sections and DNA extraction was performed. Data analysis was performed with the CNAG 3.0 software.Results226 samples (79.6%) yielded adequate virtual karyotypes for interpretation. Importantly, 43% of failed samples belong to one specific source where tissue blocks were subject to extreme temperature variation. Parameters for selecting samples for hybridization based on PCR product size range for the 10K 2.0 arrays were developed which obtained 80‐90% success rate on hybridizations. 37 samples were repeated (2 to 4 times) and in all instances results from all successful repeats from one sample showed identical virtual karyotypes. In 15 samples two or more tumor regions were assayed separately and in 53% of these, tumor heterogeneity in chromosomal imbalances was observed.ConclusionVirtual karyotyping with SNP microarrays is a robust technique that shows good performance and excellent reproducibility when applied to the analysis of FFPE tissues.
A systematic overview and meta‐analysis of genetic variation within the folate metabolic network and cardiovascular disease (CVD) risk
Authors: Wernimont Susan M. , Stover Patrick J. , Wells Martin T. , Cassano Patricia A. 
Published: June 2021

Dysfunctional folate metabolism has been implicated in chronic diseases including CVD. The relation of the methylene‐tetrahydrofolate reductase enzyme to CVD risk is the subject of several meta‐analyses, yet much less is known about variation in other folate network genes in relation to CVD. Thus, a systematic overview and meta‐analysis of genetic variation in the folate network in relation to CVD was conducted. Fifty‐two genes in the folate network were identified, representing key reactions and linked steps. Four genes had an evidence base sufficient to summarize: cystathionine‐beta‐synthase (CBS, 25 studies), methionine synthase (MTR, 16 studies), methionine synthase reductase (MTRR, 9 studies) and transcobalamin II (TCN2, 4 studies). In CBS, 844ins68 had a differential effect by CVD subtype: for heart disease the variant decreased risk (OR 0.77; 95% CI 0.6, 1.0; I2 24.2%), for stroke & other vascular disease it increased risk (OR 1.30; 95% CI 1.0, 1.7; I2 0%). In MTRR, rs1801394 increased the risk of CVD (OR 1.27; 95% CI 0.9, 1.7; I2 19.3%), and the number of publications precluded subtype analysis. For CBS rs5742905, MTR rs1805087, and TCN2 rs1801198, little or no association with CVD was observed. Thus, the association of genetic variation in the folate network with CVD differs by gene and outcome, and few variants have been studied sufficiently to allow meta‐analysis. Funding: NIH T32 DK007158‐33 (SMW).Grant Funding SourceNIH T32 DK007158‐33 (SMW)
The effect of manganese exposure on endogenous markers of oxidative stress in astrocytes
Authors: Fordahl Steve , Anderson Joel , Milatovic Dejan , Aschner Michael , Erikson Keith 
Published: June 2021

Manganese (Mn) is an essential trace element; however, accumulation of Mn in the brain can propagate cellular damage leading to neuronal dysfunction and symptoms analogous to neurodegenerative disorders (i.e. Parkinson's disease). Previously our lab has shown that iron deficiency significantly increases Mn accumulation decreasing glutathione (GSH) functionality. The resulting oxidative damage may alter the neuronal environment leading to dysfunction. Our goal is twofold; to characterize how Mn accumulation in astrocytes leads to lipid peroxidation (LP), and to test the efficacy of á‐tocopherol or N‐acetyl cysteine therapy in attenuating the production of F2Isoprostanes (F2Isop), a marker of LP. Primary rat astrocytes were treated with 100 or 300 ìM Mn with or without antioxidant therapy. GSH, F2Isop, and Mn levels were measured to assess overall oxidative stress. Mn exposure significantly increased GSH levels in the absence of antioxidant treatment (p<0.005), though no difference in GSH was seen in any antioxidant treatment compared to control. Significant increases in F2Isop (p<0.05) were present in Mn treated cells and attenuated by antioxidant pretreatment. These data imply that Mn induced LP is due to alterations in the GSH protective system, but may be mitigated by antioxidant therapy.Funded by NINDS 1R15NS061309‐01
Does vitamin D status predict outcomes of experimentally‐induced muscle pain and weakness in healthy young volunteers?
Authors: Peterson Catherine A , Ring Susan M , Dannecker Erin A 
Published: June 2021

Vitamin D receptor's presence in skeletal muscle indicates a role in muscle function and clinical symptoms of vitamin D deficiency include muscle weakness and pain. No one has yet examined the association of vitamin D status and experimentally‐induced muscle pain or weakness in healthy people.MethodsMuscle damage to the elbow flexors was induced with eccentric exercise (EE) in 27 men (mean age 22.5 yr) and 21 women (mean age 22.6 yr). Muscle pain ratings from unloaded movement and isometric contractions and peak isometric force (IF) were collected before EE and for 4 days post‐EE. Serum 25‐hydroxy vitamin D (25OHD) was assayed 2 days post‐EE. Linear regression was used to determine if 25OHD was a predictor of any outcome.ResultsSerum 25OHD did not predict any of the pain or strength measures. In men: R2 for pain ratings ranged from 0 to 0.02, and p‐values from 0.48 to 1.00. R2 for IF ranged from 0 to 0.02 and p‐values from 0.48 to 1.00. In women: R2 for pain ratings ranged from 0.01 to 0.21, and p‐values from 0.14 to 0.74 . R2 for IF ranged from 0 to 0.04 and p‐values from 0.41 to 0.90.ConclusionSerum 25OHD did not predict muscle pain or strength after EE‐induced muscle damage in young healthy men and women. Support: Dept. of Nutritional Sciences, Univ. of Missouri, CA Peterson; and National Institute of Arthritis and Musculoskeletal and Skin Diseases (KO1 AR050146) and the Univ. of Missouri, EA Dannecker.