bluuebunny/crossref_metadata_2025_split huggingface dataset:
The ACE2 Sheddase, ADAM17, is Up‐Regulated in Diabetic db/db Mice
Authors: Chodavarapu Harshita , Pedersen Kim , Lazartigues Eric 
Published: June 2021

Our previous studies demonstrated loss of ACE2 in the pancreas during progression of diabetes contributes to β‐cell dysfunction and hyperglycemia. The exact mechanism behind the reduction of ACE2 is not known. A sheddase ADAM17 (a disintegrin and metalloprotease 17), can promote cleavage of the ectodomain of ACE2. The aim of this study is to test the role of ADAM17 in the regulation of cellular ACE2 levels in a diabetic mouse model. For this purpose, we used 12 week old db/db (BKS.Cg‐Dock7<m>+/+Lepr<db>/J) mice (n=4/group) and their age‐matched heterozygous controls. Diabetic db/db mice showed hyperglycemia (db/db: 202.8 ±16.6 vs. Control: 85.5 ±10.4 mg/dl p<0.05) and increased body weight (db/db: 46.04 ±0.8 vs. Control: 26.7 ±0.7 g p<0.05). In addition, quantitative RT‐PCR showed 50% reduction (p<0.05) in INS‐2 (Insulin 2) gene expression in isolated pancreatic islets of db/db mice compared to controls. There was no difference in ACE2 and ADAM17 mRNA levels, suggesting that transcriptional regulation of these targets is not glucose sensitive. However, this was associated with a significant increase in ADAM17 activity (db/db: 36.92 ±2.12 vs. Control: 11.4 ±8.2 FU/min/µg protein p<0.05) but no significant difference (p>0.05) in ACE2 activity in the islets of db/db mice. In conclusion, while our results suggests that ADAM17 is up‐regulated in db/db diabetic mice, the role of ACE2 as a potential target remains uncertain. New transgenic mice with beta‐cells specific knockdown of ADAM17 are being developed to clarify the relationship between ACE2 and ADAM17 in type 2 diabetes.Support: American Heart Association: 12EIA8030004 and 14PRE18830012.
Attenuation of Claudin‐18 in Mouse Stomach Promotes the Development of Intramucosal Carcinoma
Authors: Zheng Yi , Wu Jessica , Muthupalani Sureshkumar , Wang Yaoyu , Ang Lay‐Hong , Fox James , Hagen Susan 
Published: June 2021

Claudin‐18 (cldn18) is a membrane‐spanning tight junction protein responsible for limiting paracellular H+ permeation in stomach. Pro‐inflammatory cytokines, particularly IL‐1β, block cldn18 expression in vitro and cldn18 is attenuated early in human and mouse gastric cancer (GC) development. Our aim was to determine the role of cldn18 in GC development. Methods: Mice with targeted deletion of the cldn18 gene (ko) were obtained and shown to lack both stomach and lung isoforms of cldn18. Neck region cells from uninfected control and ko mice at 7 wk were isolated by laser capture microdissection and the mRNA evaluated by RNA‐Seq followed by genomic pathway analysis. Control and ko mice were sham‐ or infected with H. pylori SS1 at 7 wk and tissues collected 20 and 30 wks later. Histopathology was scored on a 0‐4 scale. Results: By 7 wks of age, uninfected ko mice had limited inflammation but significant atrophy and dysplasia. The most highly upregulated genes in ko mice had in common STAT3 or STAT5 downstream effectors. By 20 wks post sham‐ or H. pylori‐ infection, tissues from ko mice showed intramucosal carcinoma of the corpus irrespective of H. pylori infection status.ConclusionsOur data suggest that the inflammation‐induced attenuation of cldn18 in GC development may be an independent tumor promoter with downstream effects, at least in part, supported by STAT activation and signaling.Funding was from the Department of Surgery and the Harvard Catalyst | The Harvard Clinical and Translational Science Center (SJH) and R01CA067463 and R01AI/RR037750 (JGF).
Targeting Disabled‐2 to Stabilize ΔF508‐CFTR
Authors: Chavez Moises , Ayyoubi Sahar , Cihil Kristine , Swiatecka‐Urban Agnes , Barnaby Roxanna , Stanton Bruce , Madden Dean 
Published: June 2021

The fatal genetic disease Cystic Fibrosis (CF) is caused by mutations in the CF Transmembrane Conductance Regulator (CFTR) gene. The most common mutation, ΔF508‐CFTR, negatively impacts the processing, gating, and stability of CFTR. Existing combination therapies elicit only modest benefit in ΔF508‐CFTR patients. Potentiators and correctors address the gating and processing defects of ΔF508‐CFTR, respectively, but do not specifically target its stability. Thus, by targeting additional aspects of the mutant CFTR life cycle we may significantly improve CF patient prognosis. Here, we present evidence for a new class of stabilizers that target CFTR half‐life. The adaptor protein Disabled‐2 (Dab2), is an essential mediator of CFTR endocytosis. The Dab2 Dab homology (DH) domain is required for Dab2 to co‐assemble in complex with CFTR, and our lab has shown that DH peptide inhibitors enhance ΔF508‐CFTR function alone and even more so when combined with correctors and potentiators. We have now used an engineered peptide with high‐affinity for the DH domain as a reporter in a fluorescence anisotropy based high‐throughput screen to identify candidate small‐molecule inhibitors. FRET and NMR are used to further characterize the intermolecular binding between the DH domain and potential stabilizers.
CB‐5083: A p97 Inhibitor Disrupts Cellular Protein Homeostasis and Shows Potent Anti‐Tumor Effects
Authors: Kumar Brajesh , Rice Julie , Djakovic Stevan , Madriaga Antonett , Wong Steve , Valle Eduardo , Menon Mk , Wang Jinhai , Soly Szerenke , Soriano Ferdie , Yao Bing , Le Moigne Ronan , Zhou Han‐jie , Wustrow David , Rolfe Mark , Anderson Daniel 
Published: June 2021

p97 is a homo‐hexameric AAA‐ATPase complex that plays vital roles in protein homeostasis, including ubiquitin‐proteasome mediated protein degradation, endoplasmic reticulum‐associated degradation (ERAD) and autophagy. ATP hydrolysis driven by p97 results in a conformational change within the homo‐hexameric complex that generates mechanical force, utilized for extracting misfolded proteins from the ER and other organelles and chaperoning a subset of those proteins to the proteasome for degradation. Since cancer cells heavily utilize the ubiquitin‐proteasome system, targeting p97 within this pathway is an attractive approach for the development of new cancer therapeutics. Here we report that CB‐5083 is a potent and specific small molecule inhibitor of p97 as a novel cancer treatment. CB‐5083 is a reversible inhibitor of p97 that binds competitively with ATP to the D2 ATPase site of p97. Mutations in or adjacent to the D2 ATPase binding site resulted in reduced potency of CB‐5083 in biochemical assays, confirming role of CB‐5083 in p97 activity by direct binding to its D2 ATPase site. CB‐5083 treatment of cells leads to accumulation of poly‐ubiquitinated proteins, retention of ERAD substrates in the ER and generation of irresolvable ER stress that in turn induces a lethal unfolded protein response (UPR). CB‐5083 is orally bioavailable and has good exposure in animal models leading to modulation of key p97‐related pathways. CB‐5083 is now being tested in the clinic as a novel therapeutic for patients with multiple myeloma (MM) and solid tumors.
Evaluation of The Effects of Organic And Aqueous Extracts of Euphorbia Poissonii on The Gene Expression of BRCA1, BRCA2 and TP53 in MCF‐7 Brest Cancer Cell
Authors: Samuel Titilola , James Babatunde , Onawoga Fatimoh , Negedu Sunday , Adekanle Kehinde , Magbagbeola Olubunmi 
Published: June 2021

Euphorbia poissonii (Euphorbiaceae) is a plant native to Northern Nigeria and it is known to possess cytotoxic properties.The possibility of the crude ethanol extract, hexane, ethyl‐acetate, chloroform, butanol and aqueous fractions to modulate the tumor suppressor genes, BRCA1, BRCA2 and TP53 were investigated. MCF‐7 cell lines were treated with crude ethanolic (CEE), hexane (HF), chloroform(CF), ethyl acetate (EF), butanol (BF) and aqueous (AF) fractions of Euphorbia poissonii and the gene expression of BRCA1, BRCA2 and TP53 were measured using semi‐quantitative RT‐PCR analysis. Results showed down‐regulation of BRCA1, up‐regulation of BRCA2 by CEE, BF, EF, AF and TP53 by HF,CF, EF respectively by the 6 panel fractions. The up‐regulation of BRCA2 and TP53 suggests that the fractions contain bioactive compounds that restored the loss of function of BRCA2 and p53 in the human breast cancer cell line, MCF‐7.
Using a Short Visual‐Text Guide to Allow Ultrasound Self‐Study by Novices
Authors: Benninger Brion , Stringer Rebecca , McLane Lisa 
Published: June 2021

IntroductionUltrasound (US) use in healthcare has grown exponentially. Number of novice users has outpaced trained users available for instruction. There is a need for an efficient teaching method providing autonomy and immediate satisfaction.Objective of this study was to assess whether novice healthcare students could utilize an US visual‐text guide (VTG) to immediately begin using an US system.MethodsLiterature search was conducted on andragogy of US VTG(s). An US VTG was created using a Fukuda Denshi UF‐760AG US system with classic and Sonivate finger probes. Step‐by‐step photos of the US system in use were compiled with succinct and minimal text instructions supplemented with multi‐media. The US VTG consisted of applying basic US principles to an US system using 3‐4 page segments per probe type. Medical students (yrs. 1‐2) were asked to review the VTG for up to 15 minutes and note their ease of use of the US system with a Likert scale 1‐4. They were allowed to reference the guide during use. Their ability to obtain diagnostic images and use the basic functions of the US system was evaluated by experts in the field.SummaryLiterature search revealed no known andragogy studies. After the allotted review time all novices were able to successfully use the VTG to achieve quality images. They reported increased confidence in their US ability compared to pre‐study levels revealed by high Likert scores. A growing gap exists between trained US users and novices in healthcare. This study created an efficient VTG that would not fatigue a user while allowing them to gain valuable probe time thus permitting growth of users independent of trained users.ConclusionThis study revealed that a novice could begin utilizing an US system using an efficient, VTG.
Gut Commensal Immunomodulatory Factors: Identification and Structure‐Function Studies
Authors: Oh Sungwhan , Erturk‐Hasdemir Deniz , Kasper Dennis 
Published: June 2021

Contribution of commensal microbiota to the host immune maturation gathers significant interests, however, their underlying mechanisms are remained to be investigated. We have focused on Bacteroides fragilis, one of the most ubiquitous residents of human gut. Establishing diverse, high‐sensitivity analysis methodologies, we have identified two commensal immunomodulatory factors, α‐galactosylceramides (BfαGCs) and a lipid anchor of polysaccharide A (PSA).Previously, we have shown that glycosphingolipids from B. fragilis can regulate host natural killer T cell (NKT) number and administration of glycosphingolipids in early stage of life can protect animals from NKT‐mediated colitis. Among vastly diverse gut microbiota, ceramides, which includes glycosphingolipids, are almost exclusively produced by order Bacteroidales; LC‐MS/MS based metabolomic screening identified that α‐galactosylceramides are even more restricted in only a few commensal species, including B. fragilis. B.fragilis produces several classes of sphingolipids with diverse acyl chain length and branching. Among them, purified BfαGCs antagonize binding of prototypic ligands to CD1d and subsequent activation of NKTs in structure‐specific manner.In addition to the previously reported immunomodulatory functions of PSA, the acid‐labile lipid anchor of PSA was critical to TLR2‐mediated IL‐10 production. MALDI‐TOF‐TOF analysis has identified that hydrophobic moiety resembles the structure of B. fragilis lipid A, with distinct difference in molecular composition, such as a degree of acylation. These results imply that PSA might bear a multiple functional moieties with distinct cellular signaling pathways.
Translational and Morphological Effects of Signalling Alcohols on C. albicans
Authors: Egbe Nkechi , Ashe Mark 
Published: June 2021

Candida albicans is a polymorphic yeast that can cause life threatening systemic infections in immunocompromised individuals. One key attribute of C. albicans that enhances pathogenicity is the capacity to switch morphology from vegetative to filamentous modes in response to specific environmental conditions. Stressful changes in such cellular conditions commonly cause a rapid inhibition of global protein synthesis leading to altered programmes of gene expression.Fusel alcohols induce hyphal/pseudohyphal growth, while farnesol, a quorum sensing alcohol, prevents this distinct form of growth. A variety of cell biological and genetic assays suggest that fusel alcohols and ethanol inhibit protein synthesis in C. albicans by targeting the translation initiation factor eIF2B, whereas farnesol inhibits protein synthesis in a manner that does not impact upon eIF2B activity. Rather biochemical and mass spectrometric analysis suggest farnesol affects the interaction of the mRNA with the small ribosomal subunit during translation initiation. Further analysis of the effect of farnesol on C. albicans transcript levels and ribosome association by next generation sequencing provide insight into genes that are differentially expressed following farnesol treatment. While genes involved in morphological differentiation, biofilm formation, cytokinesis and cell cycle were generally repressed, those involved in protein synthesis, oxidative stress and cellular respiration were upregulated. Intriguingly, the regulation of these functional categories of genes occurs in a co‐ordinated manner; at either the transcript level or at the level of ribosome association, but rarely at both transcriptional and post‐transcriptional levels for the same gene.
ApoA‐IV Regulates Cytokine Responsiveness in LPS‐challenged Macrophage Cells
Authors: Li Xiaoming , Li Zongfang , Yan Jianqun , Tso Patrick 
Published: June 2021

ApoA‐IV has an anti‐inflammatory role but it is unknown whether apoA‐IV affects inflammation cytokines induced by LPS in macrophage cells.We determined if apoA‐IV influences the secretion of cytokines stimulated by LPS in the cells.The macrophage RAW264.7 cells were pre‐treated with apoA‐IV (20µg/ml) for 1h, followed with LPS (500ng/ml) for 20 h. The culture medium was collected and RayBio® Mouse Inflammation Antibody Array G Series I was used to measure the cytokines.Both apoA‐IV and LPS or the two of them have no effect on the cytokines: POS, NEG, Lymphotactin, MCSF, MIP‐1α, MIP‐1γ, IL‐13, IL‐1β, BLC, CD30L, Eotaxin, IFN‐γ, and MIG, in 42 cytokines detected. ApoA‐IV had the trend to reduce Fas ligand, Fractalkine and Eotaxin‐2. Both apoA‐IV and LPS increased the cytokines GCSF, IL‐2, IL‐3, IL‐4, IL‐6, IL‐9, IL‐12P40/P70, GCSF, TIMP‐1, LIX, SDP‐1, TCA‐3, TECK, TIMP‐2, sTNF‐RI, sTNF‐RII, GM‐CSF, RANTES, I‐TAC, KC, MCP1,TNF‐α, TECK, IL‐17 and Leptin. Notably, TNF‐α and TECK induced by LPS were significantly inhibited by apoA‐IV. Interestingly,apoA‐IV enhanced IL‐10 and IL‐1α by itself and that induced by LPS.In conclusions, both LPS and apoA‐IV can induce many inflammation cytokines from macrophage cells, but the patterns are different. ApoA‐IV negatively or positively regulates a few cytokines induced by LPS. The mechanism involved remains to be elucidated. Supported by Program for Changjiang Scholars and Innovative Research Team (PCSIRT:1171).
Nuclear Export of Spliceosome‐discarded Intermediates
Authors: Zeng Yi , Staley Jonathan 
Published: June 2021

The precise removal of introns is essential for cell survival. To promote fidelity in nuclear pre‐mRNA splicing, the spliceosome rejects and discards suboptimal splicing substrates that have engaged the spliceosome. Although intron‐containing transcripts can be retained and degraded in the nucleus, various spliceosome‐discarded intermediates, such as mutated lariat intermediates, can be degraded in the cytoplasm. However, it is unknown why or how these suboptimal intermediates are exported for turnover.Here, we used RNA‐FISH to provide direct evidence that mutated lariat intermediates are exported into the cytoplasm and disruption of DEAH‐box ATPase Prp43p‐mediated discard of suboptimal intermediates blocks the export of mutated lariat intermediates. Further, we demonstrated that nucleoporins (Nup2p and Nup60p) and the general mRNA export receptor, Mex67p, play an essential role in the export of mutated lariat intermediates. Surprisingly, we found that Mlp1p, the nuclear retention factor, is important for the export of mutated lariat intermediates. Together, our findings establish the importance of the mRNA export pathway in transporting discarded intermediates for degradation.
User Variance in Defining the Trabecular‐Cortical Interface Using MicroCT Images
Authors: Bryce Amy , Terhune Claire , Sylvester Adam 
Published: June 2021

Micro‐computed tomography (µCT) imaging is an effective tool for quantifying bone microarchitecture. µCT images allow trabecular and cortical bone to be separated, a task critical to understanding bone mechanics. Automated algorithms are often used to facilitate this process, but are typically evaluated by comparing algorithm results to those of a single person. Such analyses do not take into account the possibility of variability among observers in defining this boundary.This study quantified the amount of inter‐observer variation in defining the cortical‐trabecular bone boundary. Ten µCT images of human femora and primate mandibles were sent to 19 researchers with interests in bone biology. Participants were asked to trace the cortical‐trabecular boundary on each image as well as to complete a questionnaire about education, training, and specific areas of interest in bone biology. For each image, boundary lines were converted to semilandmarks for use in geometric morphometric analyses. Shape variation was summarized using principle components analysis and variation among users was quantified.All of the µCT images exhibited variance in where the participants defined the cortical/trabecular interface. Often the variation was small (<10 voxels), but in some images there was considerable variation in boundary location. Analyses did not reveal significant differences (p>0.05) in boundary contours based on different levels of education or areas of expertise. The results do, however, indicate variability among bone biologists in defining the trabecular‐cortical boundary and question the validity of algorithms evaluated against a single user.
Dietary IGF‐activated Plasma Protein Alleviates Intestine Dystrophy by Induction of Tight Junction Protein in Early Weaned Rats
Authors: Kwak Minjin , Kim Jonggun , Kim Hyung‐Kwan , Ha Dong‐Jin , Whang Kwang‐Youn 
Published: June 2021

Weaning is a stressful condition for mammals and negatively affects growth performance by dystrophy of intestinal villi and crypts. Dietary plasma protein (PP) has shown the increased growth performance in early‐weaned animals and it seems to be more than nutrient content itself. Among growth factors, dietary insulin‐like growth factor (IGF) known to enhance growth performance, but bound form of IGF might reduce growth promoting effects of IGF. The effects of IGF‐activated plasma protein (aIGFPP, by de‐binding with proteins) on growth performance and gut development were studied in early‐weaned rats.Twenty‐one rats (weaned at 14‐day) were allotted into three treatments (NC, NIH‐31 diet without animal proteins; PC, NIH‐31 diet with 50 g/kg PP; and IGF, NIH‐31 diet with 3.4 g/kg aIGFPP). After 6 days, jejunum samples were collected and gene expression of inflammatory cytokines (IL‐6, TNF‐α, IL‐1β, IL‐4, IL‐12β, and IL‐10) and tight junction proteins (β‐catenin and ZO‐1) were determined by qRT‐PCR. Body weights were measured daily. And the villus heights and crypt depths were also measured in jejunum.Body weight was numerically higher in rats of PC and IGF groups than rats of NC. There was no differences in TNF‐α, IL‐1β, IL‐4, IL‐12β, and IL‐10 expression, but IL‐6 was higher in IGF group than other groups (P<0.05). Tight junction protein, ZO‐1 and β‐catenin, expression was higher in IGF group than other groups at P<0.10 and P<0.05, respectively. Jejunal villus heights of rats in IGF group were higher than rats in other groups (P<0.05) but no difference was found in crypt depth. This data indicates aIGFPP could increase gut growth and might affect growth performance in early‐weaned rats.
Super‐resolution Imaging Shows Spatial Regulation of p130Cas Phosporylation within Focal Adhesions
Authors: Elmokadem Ahmed , Moraru Ion , Yu Ji 
Published: June 2021

Cell motility is critical for physiological processes such as tissue development and remodeling as well as pathologies such as cancer metastasis. Cell motility is influenced by its surrounding matrix through biochemical and mechanical stimuli. p130Cas is a signaling molecule that has been proposed to be a mechanosensor, which responds to mechanical stimuli and mediates cell motility during the early stage of lamellipodial protrusions. p130Cas localizes to focal adhesions (FAs) and binds with its effectors via tyrosine phosphorylation of its substrate domain. Previous studies have suggested that mechanical stimuli increase p130Cas tyrosine phosphorylation and these phosphotyrosines recruit SH2‐domain containing effectors like Crk, that initiate a signaling cascade activating the small Rho‐GTPase Rac1 leading to lamellipodial protrusions.Due to spatial heterogeneity of stresses within FAs, we hypothesized that p130Cas phosphorylation is not uniform across a single FA. Spatial differences across such small structures as FAs cannot be resolved using biochemical assays or standard microscopy. We used a super resolution imaging technique, PALM (photo‐activated localization microscopy) to study the differences in p130Cas phosphorylation within individual FAs using SH2 domains of Crk as probes. Our results show punctate localization of SH2 probes at single FAs compared to uniform distribution of p130Cas.Our data suggest that p130Cas activity is spatially regulated. In the future we will look at correlations between mechanical stress within FAs and p130Cas activity. Our results will help elucidate the mechanism of mechanical regulation of p130Cas phosphorylation, and may help understand how cells sense and respond to external mechanical stimuli.